#precalculus | Mathematics | Page 175

cobalt totem Oct 10, 2019, 1:04 AM

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ooohhh

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I SEE

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so you have sqrt(1 - 0 + 0) + 1

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so 2

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and then

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0 / 2

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so 0

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epic

stuck lark Oct 10, 2019, 1:05 AM

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what's the top?

cobalt totem Oct 10, 2019, 1:05 AM

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oh waittt

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-3/2

stuck lark Oct 10, 2019, 1:05 AM

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that's it

cobalt totem Oct 10, 2019, 1:05 AM

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i forgot about - 3

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if i were doing this on paper it'd be easier haha

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so not drop a - 3

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these are fun problems

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thank you guys

stuck lark Oct 10, 2019, 1:06 AM

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you're welcome rooWink

cobalt totem Oct 10, 2019, 1:06 AM

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are these pre-calc problems? rn we're not doing limits we're just doing tirg

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trig

stuck lark Oct 10, 2019, 1:08 AM

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i'd say limits are from the first few days of a calc 1 class

cobalt totem Oct 10, 2019, 1:08 AM

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yea

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I know kind of how to do some of these problems from graphs because I took a college algebra class over the summer and we pretty much did limits without doing limits

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we found horizontal asymptotes by looking at end behavior

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which is what you do with a limit to infinity

viscid thistle Oct 10, 2019, 2:19 AM

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📎 unknown.png

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Can anyone help me out on this

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I'm not sure which one it would be

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Wouldn't that be D?

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Just wanna make sure I'm correct

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<@&286206848099549185>

normal sundial Oct 10, 2019, 2:40 AM

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Why do you say its D

viscid thistle Oct 10, 2019, 2:40 AM

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i assumed id have to find the position vs time graph

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since i need to find f(x)

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and its in velocity form

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rn

normal sundial Oct 10, 2019, 2:40 AM

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yeah

viscid thistle Oct 10, 2019, 2:40 AM

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so is it?

normal sundial Oct 10, 2019, 2:41 AM

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but that axis crosses the line before 0 right?

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the graph of f'

viscid thistle Oct 10, 2019, 2:41 AM

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hmmm

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yeah...

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dam

normal sundial Oct 10, 2019, 2:41 AM

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well that means that f has to be increasing

viscid thistle Oct 10, 2019, 2:41 AM

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would it be C?

normal sundial Oct 10, 2019, 2:41 AM

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the entire time

viscid thistle Oct 10, 2019, 2:41 AM

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oh.

normal sundial Oct 10, 2019, 2:41 AM

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after that

viscid thistle Oct 10, 2019, 2:41 AM

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B..?

normal sundial Oct 10, 2019, 2:41 AM

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if f' > 0 then what happens to f

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also

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think about what it means for f'(x) = 0

viscid thistle Oct 10, 2019, 2:42 AM

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well

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ik that when f increases, f prime x has all x

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on the x axis

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right?

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sorry its late and im tired so i cant think properly

normal sundial Oct 10, 2019, 2:43 AM

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when f increases

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f' is positive

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its all good

viscid thistle Oct 10, 2019, 2:44 AM

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so in that case, what graph would f be

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im going to assume A

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i keep changing my answer so much

normal sundial Oct 10, 2019, 2:44 AM

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You tell me

viscid thistle Oct 10, 2019, 2:44 AM

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I think it's A

normal sundial Oct 10, 2019, 2:44 AM

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ok. do you know what it means for f'(x) = 0 ?

viscid thistle Oct 10, 2019, 2:44 AM

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nvm, i found it

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it's C

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i think i understand it now.

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correcT?

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are any of those graphs right lmaop

normal sundial Oct 10, 2019, 2:45 AM

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I think its A

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but its not a good graph

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there are 2 crit points in f

viscid thistle Oct 10, 2019, 2:46 AM

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i thought it would be C...

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i think it is

normal sundial Oct 10, 2019, 2:46 AM

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it cant be c because c decreases and f' is positive

viscid thistle Oct 10, 2019, 2:46 AM

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I honestly cant see any graph being right

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tbh

normal sundial Oct 10, 2019, 2:47 AM

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its supposed to be A

viscid thistle Oct 10, 2019, 2:47 AM

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A has y=0 when -3 on the x-axis, makes no sense

normal sundial Oct 10, 2019, 2:47 AM

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f has to be increasing after f' crosses the x axis

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the crit point is at 1

formal patrol Oct 10, 2019, 2:47 AM

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looks like A to me

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why not A?

normal sundial Oct 10, 2019, 2:47 AM

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It is A

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A changes concavity at x = 1 because f' goes to zero at x = 1

viscid thistle Oct 10, 2019, 2:49 AM

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ah

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hmm

formal patrol Oct 10, 2019, 2:49 AM

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A changes concavity at x=1 because f'' is 0 at x=1

normal sundial Oct 10, 2019, 2:49 AM

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yes

viscid thistle Oct 10, 2019, 2:49 AM

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Its supposed to be A

formal patrol Oct 10, 2019, 2:49 AM

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f' goes from decreasing to increasing

viscid thistle Oct 10, 2019, 2:49 AM

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but I dont think the proportions are right

formal patrol Oct 10, 2019, 2:50 AM

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it is A

normal sundial Oct 10, 2019, 2:50 AM

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the proportions arent right

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but its still A

viscid thistle Oct 10, 2019, 2:50 AM

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yeah

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its shit graph

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so its still A

normal sundial Oct 10, 2019, 2:50 AM

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yeah i hate these questions

viscid thistle Oct 10, 2019, 2:50 AM

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even if the proportions

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suck

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?

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yeah

normal sundial Oct 10, 2019, 2:50 AM

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yeah

viscid thistle Oct 10, 2019, 2:50 AM

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alrighty well ill take the chance

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ty bois

last bloom Oct 10, 2019, 2:59 AM

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i mean i just looked at all the parts where f'(x) was flat

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and then that would be a

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even if its not very accurate

open eagle Oct 10, 2019, 3:46 AM

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📎 20191009_204431.jpg

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Why is there the gap in the middle, shouldn't it be 2 petals?

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That join at (0, 0 radians)

stuck lark Oct 10, 2019, 3:56 AM

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@open eagle your calc looks wonky. https://www.desmos.com/calculator/keqsdxjz2h

Desmos Graphing Calculator

infty

stuck ivy Oct 10, 2019, 4:24 AM

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📎 unknown.png

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I'm not quite sure how I messed up here since to turn my question into natural law I do ln(x)/ln(6)/ln(x)/ln(7)

uncut mulch Oct 10, 2019, 4:29 AM

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not ln(x)/ln(6)/ln(x)/ln(7) but
(ln(x)/ln(6)) / (ln(x)/ln(7))

stuck ivy Oct 10, 2019, 4:29 AM

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Yeah

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you're right

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I figured it out

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but it gave me a weird error

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for the last question

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📎 unknown.png

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📎 unknown.png

uncut mulch Oct 10, 2019, 4:32 AM

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show your working out

stuck ivy Oct 10, 2019, 4:33 AM

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Yeah so when I solved it I used x as the numerator out of habit

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rather than using a instead

uncut mulch Oct 10, 2019, 4:35 AM

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is your answer fixed now?

stuck ivy Oct 10, 2019, 4:37 AM

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yeah it's good

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📎 unknown.png

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does anyone know how I would solve this?

uncut mulch Oct 10, 2019, 4:46 AM

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what have you tried?

stuck ivy Oct 10, 2019, 4:48 AM

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I tried to like take out the exponent from the function and put it on the left

proven dove Oct 10, 2019, 4:49 AM

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is absolute max also relative max?

stuck ivy Oct 10, 2019, 4:49 AM

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📎 unknown.png

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I did something like this

stuck lark Oct 10, 2019, 4:50 AM

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relative and absolute extrema are NOT the same idea

proven dove Oct 10, 2019, 4:50 AM

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i changed it @stuck lark

stuck ivy Oct 10, 2019, 4:50 AM

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It wants something like a + b +c

stuck lark Oct 10, 2019, 4:50 AM

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still no

proven dove Oct 10, 2019, 4:50 AM

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so absolute max cannot also be considered a relative max?

stuck lark Oct 10, 2019, 4:51 AM

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it is POSSIBLE for some function to have global max be also a relative max but in general you shouldn't say relative and global extrema are the same

proven dove Oct 10, 2019, 4:52 AM

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ok

open eagle Oct 10, 2019, 4:52 AM

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isnt global max always a relative max, but not necessarily the other way around

stuck lark Oct 10, 2019, 4:53 AM

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not true at all

proven dove Oct 10, 2019, 4:54 AM

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📎 image001.png

uncut mulch Oct 10, 2019, 4:54 AM

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@stuck ivy can log (y^7 z^5) be written as a sum of 2 logs?

stuck ivy Oct 10, 2019, 4:55 AM

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like log(y^7) + log(z^5) ?

open eagle Oct 10, 2019, 4:55 AM

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yup I was wrong, seems absolute extrema are not considered local if at the end of a functions domain

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but an absolute extrema can be a relative extrema

proven dove Oct 10, 2019, 4:57 AM

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isn't a global max the same as abs max?

stuck lark Oct 10, 2019, 4:57 AM

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same thing

proven dove Oct 10, 2019, 4:57 AM

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nvm

summer sierra Oct 10, 2019, 5:20 AM

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A rectangular box with a square base is to have a volume of 20 cubic feet. The material for the base costs 30 cents/square foot. The material for the sides costs 10 cents/square foot. The material for the top costs 20 cents/square foot. Determine the dimensions that will yield minimum cost. Let x = length of the side of the base. Construct a rational function to help solve this problem.

summer sierra Oct 10, 2019, 5:39 AM

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Can someone help?

languid crane Oct 10, 2019, 5:54 AM

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Why is this channel full of calculus problems

timid dock Oct 10, 2019, 7:08 AM

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anyone active/online

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i really need help

willow bear Oct 10, 2019, 7:08 AM

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JustAsk

timid dock Oct 10, 2019, 7:10 AM

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📎 Screen_Shot_2019-10-10_at_12.10.21_AM.png

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compared to

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write a 4th deg polynomial with only 3 real zeros

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for the second question, i accepted that if the multiplicity was two on a zero then the zero wasn't real

willow bear Oct 10, 2019, 7:11 AM

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uh. no?

timid dock Oct 10, 2019, 7:11 AM

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ok

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i learned wrong then

willow bear Oct 10, 2019, 7:12 AM

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(x-7)^2 has one real zero of multiplicity 2

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anyway i'm gonna transcribe the problem in plaintext for my own sake so i don't have to squint every time

Write a polynomial of degree 5 with real coefficients that has two real roots, one of multiplicity 2 and one of multiplicity 1.

timid dock Oct 10, 2019, 7:13 AM

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sorry

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i was gonna type it out but i gave up

willow bear Oct 10, 2019, 7:13 AM

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yeah so

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well

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what have you tried so far for this problem

timid dock Oct 10, 2019, 7:14 AM

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i dont even understand what counts as real and imaginary

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or not real

willow bear Oct 10, 2019, 7:14 AM

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wdym, "what counts"

timid dock Oct 10, 2019, 7:16 AM

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since we have x(x-1)(x-2)(x-3)(x-4) as a 5th deg polynomial with 5 zeros, what would be considered not to be a real zero

willow bear Oct 10, 2019, 7:17 AM

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its zeroes are 0, 1, 2, 3 and 4. these are all real numbers.

timid dock Oct 10, 2019, 7:17 AM

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so if i get an irrational number then it wouldn't be a real zero?

willow bear Oct 10, 2019, 7:18 AM

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why would it not be? irrational numbers are still real.

timid dock Oct 10, 2019, 7:18 AM

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i meant imaginary

willow bear Oct 10, 2019, 7:18 AM

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x^2 - 2 has -sqrt(2) and sqrt(2) as zeroes. these are both real numbers.

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ok, i didn't know you meant imaginary when you said irrational.

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if a zero is not real, then it is not real.

timid dock Oct 10, 2019, 7:19 AM

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sry im sleepy

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so (x+1)(x-1)(x+2)(x+sqrt(-1)) would answer the second question

willow bear Oct 10, 2019, 7:20 AM

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hnnfgngh

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no

timid dock Oct 10, 2019, 7:20 AM

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now?

willow bear Oct 10, 2019, 7:20 AM

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first off, please write i, not sqrt(-1).

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second, what you wrote is not a polynomial with real coefficients.

timid dock Oct 10, 2019, 7:20 AM

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im not sure if mty teacher can accept that

willow bear Oct 10, 2019, 7:20 AM

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accept what

timid dock Oct 10, 2019, 7:21 AM

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me writing x+i

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whatever

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go on

willow bear Oct 10, 2019, 7:21 AM

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why would she not accept that though

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i mean, aside from your polynomial not having real coefficients

timid dock Oct 10, 2019, 7:21 AM

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she gets picky idk

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the question "write a 4th deg polynomial with only 3 real zeros" did not ask for it

willow bear Oct 10, 2019, 7:22 AM

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well ok if it didn't mention real coefficients then that's fine i suppose

timid dock Oct 10, 2019, 7:22 AM

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ah ok

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how would i do the first question then

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do I find the factored form and then multiply?

willow bear Oct 10, 2019, 7:23 AM

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yes, construct the polynomial by its factorization first

timid dock Oct 10, 2019, 7:23 AM

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hmm

willow bear Oct 10, 2019, 7:23 AM

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one possible polynomial is (x-3)(x-4)^2(x^2+1)

timid dock Oct 10, 2019, 7:24 AM

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does the x^2 count towards the degree of 5?

willow bear Oct 10, 2019, 7:24 AM

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...what do you mean, "does it count"

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why would it possibly not count

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this polynomial is quintic

timid dock Oct 10, 2019, 7:25 AM

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oh wait nevermind

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i didnt think about that

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yeah yeah sorry

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see that's my problem. i never think about the simplest things when doing math problems

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thanks though

willow bear Oct 10, 2019, 7:28 AM

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yeah you seem to overthink things a lot

timid dock Oct 10, 2019, 7:29 AM

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i agree

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also

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what does tuong à prix réduit mean

willow bear Oct 10, 2019, 7:29 AM

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"discount Tuong"

timid dock Oct 10, 2019, 7:29 AM

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what does that mean

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im under the impression that tuong is a family name

willow bear Oct 10, 2019, 7:30 AM

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it's the name of another honorable

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@frozen needle

timid dock Oct 10, 2019, 7:30 AM

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ah ok

willow bear Oct 10, 2019, 7:30 AM

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it's a bit of an injoke

timid dock Oct 10, 2019, 7:31 AM

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is it a chain of people à prix réduit

willow bear Oct 10, 2019, 7:31 AM

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yes. but i think it currently ends at @spring thunder

timid dock Oct 10, 2019, 7:32 AM

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how far does it even go

spring thunder Oct 10, 2019, 7:32 AM

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4ppl

timid dock Oct 10, 2019, 7:32 AM

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im only seeing 4

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a ok

willow bear Oct 10, 2019, 7:33 AM

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SA isn't around anymore though 😢

timid dock Oct 10, 2019, 7:33 AM

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how long have you been learning french

willow bear Oct 10, 2019, 7:34 AM

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about a year

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i'm shit at it

timid dock Oct 10, 2019, 7:34 AM

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i'm seeing a lot of corrections from you

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it'll come in time

willow bear Oct 10, 2019, 7:34 AM

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well i mean i'm shit at actually SPEAKING french

timid dock Oct 10, 2019, 7:34 AM

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just practice speaking a lot

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well

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hang out in the voice chats more

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theyre talking right now

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but mostly in english

timid dock Oct 10, 2019, 8:19 AM

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ok

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more questions

alpine cove Oct 10, 2019, 8:20 AM

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@willow bear can we divide vector with another vector

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?

timid dock Oct 10, 2019, 8:20 AM

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📎 Screen_Shot_2019-10-10_at_1.20.32_AM.png

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why is x-2 an element of the domain of f(x)

willow bear Oct 10, 2019, 8:21 AM

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because x-2 is acting as the input to f

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so it must be in its domain

timid dock Oct 10, 2019, 8:21 AM

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oh

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so i can look at it as g(x)= h(f(j(x)))

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j(x) being x-2

willow bear Oct 10, 2019, 8:22 AM

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if you wish

timid dock Oct 10, 2019, 8:23 AM

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got it

willow bear Oct 10, 2019, 8:23 AM

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@alpine cove no, that doesn't make any sense

timid dock Oct 10, 2019, 8:25 AM

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📎 Screen_Shot_2019-10-10_at_1.25.23_AM.png

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why is the range from [0,4]

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oh

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nvm

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forget i asked

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why do we change f(x) to |f(x)| when finding the range

willow bear Oct 10, 2019, 8:28 AM

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what do you mean

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we're finding the range of |f(x)|

timid dock Oct 10, 2019, 8:28 AM

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oh is it that easy

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i dont understand how the range is being solved in b

📎 Screen_Shot_2019-10-10_at_1.20.32_AM.png

willow bear Oct 10, 2019, 8:31 AM

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which step are you confused about

timid dock Oct 10, 2019, 8:31 AM

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are we building on f(x-2)?

willow bear Oct 10, 2019, 8:31 AM

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wdym by "building on"

timid dock Oct 10, 2019, 8:31 AM

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and why do we only use the f(x-2)

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like adding the 0.5

willow bear Oct 10, 2019, 8:32 AM

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the 0.5 is not being added

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it is being multiplied

timid dock Oct 10, 2019, 8:32 AM

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thats what i meant but

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just completing it backwards

willow bear Oct 10, 2019, 8:32 AM

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but yes we are starting with f(x-2) and buidling up to g(x) from there

timid dock Oct 10, 2019, 8:33 AM

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why do we do that and not the other way around

willow bear Oct 10, 2019, 8:36 AM

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we know the range of f

timid dock Oct 10, 2019, 8:36 AM

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so if we dont know the range of f we cant do anything

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given that they don't give us anything to work with

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holy sh*t pg&e is gonna make me cry

willow bear Oct 10, 2019, 8:39 AM

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pg&e?

timid dock Oct 10, 2019, 8:39 AM

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no power for half a week

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it's an american thing

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pacific gas and electric

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cutting off power in california bc of wildfire risk

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not all at once

flint stirrup Oct 10, 2019, 9:00 AM

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@timid dock LOL im the part of cali not in that bucket

timid dock Oct 10, 2019, 9:02 AM

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in Domain g = {x| |x-3| ∈ [0,∞)} why is it all real numbers

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is it because there is an absolute value

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@flint stirrup so cal or middle of the valley/bay area/san jose not foothills

willow bear Oct 10, 2019, 9:05 AM

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yes the absolute value of anything is in [0, +∞)

timid dock Oct 10, 2019, 9:06 AM

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but not all real numbers are >= 0

willow bear Oct 10, 2019, 9:07 AM

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so what

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|x-3| ≥ 0 is always true

timid dock Oct 10, 2019, 9:07 AM

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why is the domain of g all real numbers

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one sec

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sry i didnt give the entire question

willow bear Oct 10, 2019, 9:07 AM

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|x-3| ≥ 0 is true for any real value of x

timid dock Oct 10, 2019, 9:07 AM

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📎 Screen_Shot_2019-10-10_at_2.07.41_AM.png

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📎 Screen_Shot_2019-10-10_at_2.08.15_AM.png

willow bear Oct 10, 2019, 9:08 AM

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yeah, sqrt(|x-3|) is defined for all real x since |x-3| ≥ 0 always

timid dock Oct 10, 2019, 9:09 AM

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ohh

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i always get the order wrong

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📎 Screen_Shot_2019-10-10_at_2.12.25_AM.png

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how would you solev for the domain of g(x)

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no need to type the answer just tell me how you would do it

willow bear Oct 10, 2019, 9:15 AM

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the only point not in the domain of g is the point which makes |x-3| = 0

timid dock Oct 10, 2019, 9:16 AM

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so as long as |x-3| is not 0

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|x-3| != 0 would be an acceptable domain?

willow bear Oct 10, 2019, 9:16 AM

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don't be obtuse

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don't write it that way

timid dock Oct 10, 2019, 9:16 AM

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well

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=/= is kinda long

willow bear Oct 10, 2019, 9:17 AM

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that isn't what i'm talking about

timid dock Oct 10, 2019, 9:17 AM

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oh

willow bear Oct 10, 2019, 9:17 AM

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!= for ≠ is fine

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what isn't fine is that you insist on not writing this thing as x != 3

timid dock Oct 10, 2019, 9:18 AM

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i was gonna say -3 < x < 3

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wait wait

willow bear Oct 10, 2019, 9:18 AM

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no!

timid dock Oct 10, 2019, 9:19 AM

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sorry

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do i only have to add 3 to each side to get that

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or do i also consider the |x-3| < 0 part

willow bear Oct 10, 2019, 9:20 AM

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are you being serious rn

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|x-3| = 0 has only one solution

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x=3

timid dock Oct 10, 2019, 9:21 AM

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its 2 am and i cant think straight

willow bear Oct 10, 2019, 9:21 AM

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why are you doing math at 2 am

timid dock Oct 10, 2019, 9:21 AM

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no idea

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i dont understand anything and it bothers me

willow bear Oct 10, 2019, 9:21 AM

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go get some sleep ffs

timid dock Oct 10, 2019, 9:22 AM

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aaggh

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so the domain is just x != 3

willow bear Oct 10, 2019, 9:22 AM

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go. get. some. mother. fucking. sleep. 2 am. is. not. a. time. to. do. math.

timid dock Oct 10, 2019, 9:22 AM

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please just 5 more minutes

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what do i do with [-1,0)U(0,2]

📎 Screen_Shot_2019-10-10_at_2.12.25_AM.png

willow bear Oct 10, 2019, 9:24 AM

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no goddamn clue, it seems really fucking irrelevant given how g doesn't involve f at all

timid dock Oct 10, 2019, 9:24 AM

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got it

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how about the range of g

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am i still building off of |x-3|

willow bear Oct 10, 2019, 9:26 AM

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the problem is poorly written

timid dock Oct 10, 2019, 9:27 AM

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the teacher is extremely ambiguous sometimes

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well i guess 5 minutes is up

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im gonna go sleep now

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thanks for the help

alpine cove Oct 10, 2019, 9:30 AM

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Lol

river kindle Oct 10, 2019, 12:25 PM

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Seems like graph translations regarding base function f of x

trail badge Oct 10, 2019, 3:55 PM

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,w graph y=|(1/(|x-3|))-2|

obsidian monolithBOT Oct 10, 2019, 3:55 PM

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📎 wolf.png

Display results online and refine query

trail badge Oct 10, 2019, 3:59 PM

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Just for curiosity

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zoomEyes

hollow bluff Oct 10, 2019, 6:33 PM

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is this correct?

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📎 unknown.png

limber bone Oct 10, 2019, 6:35 PM

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vertex (-b/2a,f(-b/2a))

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xintercepts solve x^2+10x+21

hollow bluff Oct 10, 2019, 6:36 PM

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oh wait did i get it wrong?

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im used that formula

hollow bluff Oct 10, 2019, 6:53 PM

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📎 unknown.png

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Is this correct?

willow bear Oct 10, 2019, 6:54 PM

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,w x^3 - 6x^2 + 11x - 10 = 0

obsidian monolithBOT Oct 10, 2019, 6:54 PM

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📎 wolf.png

Display results online and refine query

willow bear Oct 10, 2019, 6:54 PM

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nope

hollow bluff Oct 10, 2019, 6:54 PM

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how would I solve this problem?

serene heath Oct 10, 2019, 6:55 PM

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How did u get that

willow bear Oct 10, 2019, 6:55 PM

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well

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this

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how did you end up at that polynomial

hollow bluff Oct 10, 2019, 6:56 PM

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Somebody in class was explaining it to me

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and he said he got that but i still dont know how to do it

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so that's why I came here

willow bear Oct 10, 2019, 6:56 PM

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so you copied this from someone else?

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without knowing how it was arrived at, at all?

hollow bluff Oct 10, 2019, 6:57 PM

#

He tried explaining it but I just didnt understand his process

#

So what are the right steps to solving this?

#

wait

willow bear Oct 10, 2019, 6:58 PM

#

dispel from your head the notion that there is always a uniquely defined set of "right steps" to do a given problem.

hollow bluff Oct 10, 2019, 6:59 PM

#

ok

#

let me try at this one more time

#

📎 unknown.png

#

Is this correct?

#

📎 20191010_150147.jpg

#

That is how i got to it

#

Sorry its flipped its from my phone

willow bear Oct 10, 2019, 7:02 PM

#

,rotate -90

obsidian monolithBOT Oct 10, 2019, 7:02 PM

#

📎 631929452267438080.png

hollow bluff Oct 10, 2019, 7:02 PM

#

oh that's helpful

willow bear Oct 10, 2019, 7:02 PM

#

um

#

yeah no

#

this is wrong

hollow bluff Oct 10, 2019, 7:03 PM

#

oh well then

willow bear Oct 10, 2019, 7:03 PM

#

for starters, this has 0 as a root. and also fails to have 2+i or 2-i as roots.

#

p sure you fucked up with the minus signs here, both in placement and in accidental omission

hollow bluff Oct 10, 2019, 7:03 PM

#

oh

#

ok how do I solve it then?

willow bear Oct 10, 2019, 7:04 PM

#

well

#

let me ask you this

#

how did you arrive at what you wrote

hollow bluff Oct 10, 2019, 7:05 PM

#

well to get zeros you must = the equation to 0

#

So if the zeros are 2, and 2+i

limber bone Oct 10, 2019, 7:05 PM

#

complex roots

#

always come as pairs

hollow bluff Oct 10, 2019, 7:05 PM

#

then (x-2) has a zero of 2

willow bear Oct 10, 2019, 7:05 PM

#

@limber bone please do not interrupt!!!!

limber bone Oct 10, 2019, 7:05 PM

#

lol

willow bear Oct 10, 2019, 7:06 PM

#

ok @hollow bluff so far so good

#

a factor of (x-2) gives you 2 as a zero

#

that is correct

hollow bluff Oct 10, 2019, 7:06 PM

#

alright

#

so I tried to recall what my teacher said about the i equations and i thought [x(x(2+i)] was right

willow bear Oct 10, 2019, 7:07 PM

#

um

#

"the i equations"?

#

first off

hollow bluff Oct 10, 2019, 7:07 PM

#

the complex zeros

willow bear Oct 10, 2019, 7:07 PM

#

"2+i" isn't an equation

#

an equation has, first and foremost, an equals sign

#

why else would it be called an equation

hollow bluff Oct 10, 2019, 7:07 PM

#

yea I just couldnt find the right word

#

sorry

willow bear Oct 10, 2019, 7:08 PM

#

it's very important that you know the right word(s).

#

otherwise, you will not be able to communicate well.

hollow bluff Oct 10, 2019, 7:08 PM

#

oh ok

#

is it a complex zero?

willow bear Oct 10, 2019, 7:08 PM

#

second, it's not like complex numbers are that different from real numbers

#

the corresponding factor would be (x - (2+i)), plain and simple.

#

but then, you'll want the conjugate too, since the polynomial has to have real coefficients. so (x - (2-i)) is your third factor.

hollow bluff Oct 10, 2019, 7:09 PM

#

Oh ok so i messed up with the subtraction sign and its placement

willow bear Oct 10, 2019, 7:09 PM

#

all that's left is to multiply these three together.

hollow bluff Oct 10, 2019, 7:10 PM

#

ok let me write it out

#

so I have a question

#

are brackets necessary?

willow bear Oct 10, 2019, 7:11 PM

#

what brackets

hollow bluff Oct 10, 2019, 7:11 PM

#

my teachers uses [ ]

willow bear Oct 10, 2019, 7:11 PM

#

oh, do you mean [] vs ()?

hollow bluff Oct 10, 2019, 7:11 PM

#

[x - (2-i)]

#

that's how he would have written it

willow bear Oct 10, 2019, 7:11 PM

#

the only difference is aesthetic

hollow bluff Oct 10, 2019, 7:11 PM

#

ah ok

#

unless its about inequalities

#

(-infinity, 7]

#

right?

willow bear Oct 10, 2019, 7:12 PM

#

[] have a different meaning as part of interval notation, yes.

hollow bluff Oct 10, 2019, 7:15 PM

#

📎 unknown.png

#

thats right

#

unless I dont know how to multiply

#

,w x^3 - 6x^2 + 13x - 10 = 0

obsidian monolithBOT Oct 10, 2019, 7:16 PM

#

📎 wolf.png

Display results online and refine query

hollow bluff Oct 10, 2019, 7:16 PM

#

ayyyy

#

thank you ann

lament garden Oct 10, 2019, 8:53 PM

#

Hi i need help

#

📎 image0.jpg

spring thunder Oct 10, 2019, 8:56 PM

#

well, what could prevent 4/(x²+7x-8) from being defined?

lament garden Oct 10, 2019, 8:58 PM

#

Do i have to make the x^2 + 7x -8 equal to 0? Sorry it’s that my teacher really dosen’t teach so i have to do the things by myself

spring thunder Oct 10, 2019, 8:59 PM

#

yeah if the denominator is 0 you're pretty screwed indeed

lament garden Oct 10, 2019, 8:59 PM

#

Oh

#

📎 image0.jpg

#

Sorry for my handwriting is it like that?

serene heath Oct 10, 2019, 9:02 PM

#

Na

lament garden Oct 10, 2019, 9:02 PM

#

It’s not?

serene heath Oct 10, 2019, 9:02 PM

#

Expand it out

lament garden Oct 10, 2019, 9:04 PM

#

How?

grim current Oct 10, 2019, 9:11 PM

#

Let's go through your original expression. You have (x^2 + 7x - 8) in the denominator.

#

But first, I'll ask you a question. Let's say you have 2 apples, and there are 0 people to distribute it to. Does it make sense to distribute them?

#

@lament garden

lament garden Oct 10, 2019, 9:38 PM

#

Oh my bad i had to go eat

grim current Oct 10, 2019, 9:53 PM

#

Dw. So, does it make sense?

lament garden Oct 10, 2019, 9:58 PM

#

yeah

grim current Oct 10, 2019, 9:59 PM

#

Why?

#

Note you have no people to distribute it to.

#

It could be written as "2/0". A division that shows 2 apples are being distributed among 0 people.

#

But it doesn't make sense to do such division if you don't have - in this case - someone to divide it by (or distribute it to).

#

Do you get it?

green zenith Oct 10, 2019, 11:12 PM

#

how do we solve 5^(2log5(3)+log5(2))?

#

im familiar with the rules of the logarithm but logarithm in the exponents are very confusing to me

uncut mulch Oct 10, 2019, 11:15 PM

#

how well do you know your exponent laws?

green zenith Oct 10, 2019, 11:17 PM

#

about average

uncut mulch Oct 10, 2019, 11:17 PM

#

do you have an idea of what your first step should be?

green zenith Oct 10, 2019, 11:18 PM

#

yeah i think i got it a little bit now

#

the product rule of logarithm

#

the power rule, first, then product rule

#

and one of the properties of logarithm

#

ah i got it now

uncut mulch Oct 10, 2019, 11:19 PM

#

nice

green zenith Oct 10, 2019, 11:20 PM

#

thanks

green zenith Oct 11, 2019, 12:52 AM

#

is there a way to simplify (-5/log(2/3))log2?

#

i was trying to solve an equation and im stuck there

#

i have to find the equation of y=c+b.loga(x) that contains the two points (2,4) and (3,9)

#

so i minus both equations 4-9=c-c+blog2-blog3

#

which gets me b = -5/log(2/3)

#

then i use one of the points of the graph to solve the equation and put b in it

#

4=c+(-5/log(2/3))log2

#

here is where i'm stuck. could the two logs be divided normally?

clever agate Oct 11, 2019, 6:06 AM

#

📎 unknown.png

#

How do you get that?

willow bear Oct 11, 2019, 6:09 AM

#

$(4-\sqrt{5})^2 = 16 + 5 - 2 \cdot 4 \cdot \sqrt{5}$

obsidian monolithBOT Oct 11, 2019, 6:09 AM

#

Ann:

📎 183668144404037632.png

alpine cove Oct 11, 2019, 6:24 AM

#

f(x)=x^2 is a algebraic function ,g(x) =sinx is a trig f then what is h(x)=x^2+sinx

willow bear Oct 11, 2019, 6:26 AM

#

neither

#

as in, there's no named class it falls under

alpine cove Oct 11, 2019, 6:26 AM

#

What are these types of f called

willow bear Oct 11, 2019, 6:26 AM

#

there is no name

alpine cove Oct 11, 2019, 6:27 AM

#

Ok.

#

Also

#

Lets say $h(x)=f(x)+g(x)+k(x)$ then the domain is $D_f \cap D_g \cap D_k$ .

obsidian monolithBOT Oct 11, 2019, 6:38 AM

#

Born Killer:

📎 631576009526738944.png

alpine cove Oct 11, 2019, 6:38 AM

#

?

#

D_n represents domain of n(k)

willow bear Oct 11, 2019, 6:38 AM

#

yes

alpine cove Oct 11, 2019, 6:39 AM

#

Ok

alpine cove Oct 11, 2019, 7:28 AM

#

${x:x , x^2=9 ,2x=4 }$ does that comma mean intersection?

obsidian monolithBOT Oct 11, 2019, 7:29 AM

#

Born Killer:

📎 631576009526738944.png

heady jewel Oct 11, 2019, 7:31 AM

#

you have 2 commas

alpine cove Oct 11, 2019, 7:33 AM

#

The comma between x^2=9 and 2x=4

#

@heady jewel

willow bear Oct 11, 2019, 7:53 AM

#

uh

#

this is a very weird way to describe the empty set but sure commas in this context mean AND

alpine cove Oct 11, 2019, 8:31 AM

#

Yes that what i wanted to ask

green zenith Oct 11, 2019, 2:10 PM

#

When equating exponents, do we always use ln and not log?

hard hornet Oct 11, 2019, 2:10 PM

#

give an example

green zenith Oct 11, 2019, 2:11 PM

#

Like 5^x=7

hard hornet Oct 11, 2019, 2:12 PM

#

you can use ln, or log base n, as long as it's consistent

#

but ln is slightly more preferred

green zenith Oct 11, 2019, 2:13 PM

#

What do you mean by log base n?

hard hornet Oct 11, 2019, 2:13 PM

#

$\log_2(x)$

obsidian monolithBOT Oct 11, 2019, 2:13 PM

#

MemesPlease:

📎 190017172074921986.png

hard hornet Oct 11, 2019, 2:13 PM

#

lemme generalze

#

$\log_n(x)$

obsidian monolithBOT Oct 11, 2019, 2:13 PM

#

MemesPlease:

📎 190017172074921986.png

hard hornet Oct 11, 2019, 2:13 PM

#

any base

#

ln is base e

green zenith Oct 11, 2019, 2:14 PM

#

So as long as im using the same base for both sides?

hard hornet Oct 11, 2019, 2:14 PM

#

yup

green zenith Oct 11, 2019, 2:14 PM

#

But isnt log(x) not equals to ln(x)?

hard hornet Oct 11, 2019, 2:15 PM

#

mmm not quite

#

$\log_e(x) = \ln(x)$

obsidian monolithBOT Oct 11, 2019, 2:15 PM

#

MemesPlease:

📎 190017172074921986.png

hard hornet Oct 11, 2019, 2:15 PM

#

when you are taking the logarithm of something, the base matters

#

$log_2(16) = 4$

#

while

obsidian monolithBOT Oct 11, 2019, 2:15 PM

#

MemesPlease:

📎 190017172074921986.png

hard hornet Oct 11, 2019, 2:15 PM

#

$log_4(16) = 2$

obsidian monolithBOT Oct 11, 2019, 2:15 PM

#

MemesPlease:

📎 190017172074921986.png

hard hornet Oct 11, 2019, 2:16 PM

#

it matters

willow bear Oct 11, 2019, 2:17 PM

#

\log

hard hornet Oct 11, 2019, 2:17 PM

#

mb

green zenith Oct 11, 2019, 2:19 PM

#

Ahhh

#

It was confusing me because the calculator is not posting the same answers

#

I thought ln(7)/ln(5) is not equal to log(7)/log(5)

willow bear Oct 11, 2019, 2:21 PM

#

ln(7)/ln(5) IS equal to log(7)/log(5).

green zenith Oct 11, 2019, 2:27 PM

#

Ahhhh okay

#

My calculator had me confused

#

Thanks

hard hornet Oct 11, 2019, 2:33 PM

#

yes they're equal, but the base matters, in the case of comparing logs, they're not equal, but if you did something like what u did above, theyre the same

rugged nimbus Oct 11, 2019, 2:47 PM

#

Help me polar coordinates so hard

willow bear Oct 11, 2019, 2:47 PM

#

what exactly are you finding hard about polar coordinates

#

is there a problem that involves them that you're stuck on

rugged nimbus Oct 11, 2019, 2:48 PM

#

pensivebread

willow bear Oct 11, 2019, 2:49 PM

#

don't advertise your questions in other channels, as per the rules
don't ping me out of left field like this

viscid thistle Oct 11, 2019, 2:50 PM

#

oh srry but fluffyy was also putting his/her question in 2 channels even though the channel i put in my question first then she put in hers

rugged nimbus Oct 11, 2019, 2:50 PM

#

Why u dragging me

#

U alr send it so not get scrolled again

viscid thistle Oct 11, 2019, 2:51 PM

#

cause u posted ur exact same question in questions-B and questions-y

prisma prairie Oct 11, 2019, 4:32 PM

#

📎 image0.jpg

#

hi can someone let me know what i’m doing wrong

willow bear Oct 11, 2019, 4:32 PM

#

third line

#

$e^{a+b} \neq e^a + e^b$

obsidian monolithBOT Oct 11, 2019, 4:33 PM

#

Ann:

📎 183668144404037632.png

viscid thistle Oct 11, 2019, 7:02 PM

#

https://gyazo.com/f6e0121444d848248521f384bdcb9530

Gyazo

#

im confused as to why the angle was subtracted from 360

#

the vector lies in the third quadrant, shouldnt we use 180 + theta?

willow bear Oct 11, 2019, 7:03 PM

#

cos(180°+θ) is not equal to cos(θ) so you can't do that

viscid thistle Oct 11, 2019, 7:03 PM

#

im talking about the direction of angle

#

not cos(180+theta)

#

last line beta = 360 - arccos(...)

#

why isnt it beta = 180 + arccos(...)

#

the vector lies within the third quadrant

willow bear Oct 11, 2019, 7:05 PM

#

well for starters arccos(negative value) lies in quadrant 2

viscid thistle Oct 11, 2019, 7:08 PM

#

so if the angle lies within quadrant 2 we subtract it from 360?

willow bear Oct 11, 2019, 7:10 PM

#

no

#

subtracting the angle from 360° preserves its cosine

#

cos(360°-x) = cos(x)

#

but if x is in quadrants 1 or 2 then 360°-x is in quadrants 4 or 3 resp

green zenith Oct 11, 2019, 7:44 PM

#

when estimating large numbers, do we always use log K?

#

for example K=e^700

#

do we always log both side instead of using ln?

willow bear Oct 11, 2019, 7:48 PM

#

well you want to estimate

#

so at least to get an order of magnitude estimation yeah you'll need decimal log

green zenith Oct 11, 2019, 7:50 PM

#

Is it because log have base 10 that we use it for estimating?

willow bear Oct 11, 2019, 7:54 PM

#

yes

green zenith Oct 11, 2019, 7:58 PM

#

Okay

#

Thanks

lyric cliff Oct 11, 2019, 11:32 PM

#

Hey, How do I find the average rate of change of f(x)=2^x? Without an interval given.

hearty storm Oct 11, 2019, 11:36 PM

#

would this be true or false?

📎 unknown.png

proud sparrow Oct 12, 2019, 12:04 AM

#

@lyric cliff well, maybe you need to assume an interval [a, b]

#

can we see the original question?

#

@hearty storm what do you think? How do you convert?

hearty storm Oct 12, 2019, 12:05 AM

#

i just figured it out 😛

#

thank you tho

#

@proud sparrow

hollow bluff Oct 12, 2019, 2:41 AM

#

how would i attempt to solve this

📎 unknown.png

willow bear Oct 12, 2019, 2:47 AM

#

what have you tried

#

and which part is confusing you

hollow bluff Oct 12, 2019, 2:47 AM

#

I dont know how to attempt it

#

like would another zero be -3-2i

river kindle Oct 12, 2019, 2:48 AM

#

I believe so. imaginary zeroes typically have a conjugate

hollow bluff Oct 12, 2019, 2:48 AM

#

that's what im thinking

willow bear Oct 12, 2019, 2:48 AM

#

it's not "typically"

#

if your polynomial has real coefficients, then its nonreal zeroes ALWAYS come in conjugate pairs

hollow bluff Oct 12, 2019, 2:49 AM

#

ok

river kindle Oct 12, 2019, 2:49 AM

#

Well, I just learned this stuff last chapter, so I spoke without confidence on the always. 😛

willow bear Oct 12, 2019, 2:49 AM

#

-3i would have been a valid answer to a as well

hollow bluff Oct 12, 2019, 2:49 AM

#

alright so I get that part now

#

I wasnt confident with my answer

willow bear Oct 12, 2019, 2:50 AM

#

so you know that R has 4 nonreal zeroes already

patent beacon Oct 12, 2019, 2:50 AM

#

You can't get real coefficients without having the conjugate as a root as well, to give reasoning

willow bear Oct 12, 2019, 2:50 AM

#

you're gonna need that info to do b

hollow bluff Oct 12, 2019, 2:50 AM

#

4 nonreal zeros because of the 3i and -3+2i right?

willow bear Oct 12, 2019, 2:50 AM

#

3i, -3+2i and their conjugates

#

yes

hollow bluff Oct 12, 2019, 2:50 AM

#

ok

patent beacon Oct 12, 2019, 2:51 AM

#

You can always have others too

#

That they're just not telling you about

hollow bluff Oct 12, 2019, 2:51 AM

#

ok wait give me a second

#

Writing this down

river kindle Oct 12, 2019, 2:51 AM

#

Well, they're asking maximum, so I wouldn't get hung up on that technicality as far as answering.

hollow bluff Oct 12, 2019, 2:52 AM

#

So if i understand this then if the polynomial has real coefficients then its nonreal zeroes always will have conjugate pairs

#

and because we singled out 4 nonreal zeroes we can solve B

patent beacon Oct 12, 2019, 2:52 AM

#

Yes, exactly

hollow bluff Oct 12, 2019, 2:53 AM

#

so is it because 11-4= 7 real zeroes im allowed to answer B?

river kindle Oct 12, 2019, 2:53 AM

#

That would be how I would answer b, myself

willow bear Oct 12, 2019, 2:53 AM

#

yes there are 7 more zeroes that haven't been pinned down and it's impossible for there to be more than 7 real ones

hollow bluff Oct 12, 2019, 2:53 AM

#

alright

willow bear Oct 12, 2019, 2:53 AM

#

so yes b is 7

hollow bluff Oct 12, 2019, 2:54 AM

#

and C is 4

patent beacon Oct 12, 2019, 2:54 AM

#

Nope, you can have more complex zeroes

river kindle Oct 12, 2019, 2:54 AM

#

I don't think so. It's asking for max

hollow bluff Oct 12, 2019, 2:54 AM

#

o

#

what is one way of finding the other nonreal zeros

river kindle Oct 12, 2019, 2:55 AM

#

And you need at least one real for the conjugate stuff to be true, if I understand it.

willow bear Oct 12, 2019, 2:55 AM

#

you don't need to find them

#

but what you do know is that they come in pairs

hollow bluff Oct 12, 2019, 2:55 AM

#

alright

willow bear Oct 12, 2019, 2:55 AM

#

so there's gonna be an even number of them

#

bc yknow

#

pairs

hollow bluff Oct 12, 2019, 2:55 AM

#

mhm

willow bear Oct 12, 2019, 2:56 AM

#

so with 11 zeroes total...

hollow bluff Oct 12, 2019, 2:56 AM

#

so would that mean instead of 7 real zeroes one isnt part of a pair?

#

so would that one be a nonreal

willow bear Oct 12, 2019, 2:56 AM

#

yes you'll always have one real zero

#

uh no

patent beacon Oct 12, 2019, 2:56 AM

#

These would have to be different polynomials

willow bear Oct 12, 2019, 2:57 AM

#

the zero that isn't part of a pair IS real

hollow bluff Oct 12, 2019, 2:57 AM

#

Oh ok

patent beacon Oct 12, 2019, 2:57 AM

#

The one with 7 real zeroes is not the same one with max complex zeroes

hollow bluff Oct 12, 2019, 2:57 AM

#

alright

#

so with that all explained to me What i understand is that I dont have to find the unreal numbers right?

#

but how would i find the total number of unreal numbers

willow bear Oct 12, 2019, 2:59 AM

#

"unreal"

hollow bluff Oct 12, 2019, 2:59 AM

#

oh nonreal

#

my bad

willow bear Oct 12, 2019, 2:59 AM

#

okay so like

#

the nonreal zeroes of your polynomial come in pairs

#

and there's 11 of them total

hollow bluff Oct 12, 2019, 2:59 AM

#

22?

willow bear Oct 12, 2019, 2:59 AM

#

no

#

11 zeroes

#

not 11 pairs

hollow bluff Oct 12, 2019, 2:59 AM

#

yes

#

ah my bad

willow bear Oct 12, 2019, 3:00 AM

#

if you have 11 objects and you're arranging them in pairs, how many pairs can you make

hollow bluff Oct 12, 2019, 3:00 AM

#

5

#

with one leftover

willow bear Oct 12, 2019, 3:00 AM

#

yes

#

so

#

so if your nonreal zeroes form 5 conjugate pairs

#

and the eleventh zero is real

hollow bluff Oct 12, 2019, 3:01 AM

#

oh

#

so 5 is the maximum of nonreal zeroes

willow bear Oct 12, 2019, 3:01 AM

#

no

hollow bluff Oct 12, 2019, 3:01 AM

#

wait 10

willow bear Oct 12, 2019, 3:01 AM

#

5 PAIRS

#

yes

hollow bluff Oct 12, 2019, 3:01 AM

#

my bad

#

I was thinking 5 pairs

#

sorry

#

so this would be correct

📎 unknown.png

#

so if we had a degree of 15 then we would have 7 pairs making 14 the maximum number of nonreal zeros

#

Thank you ann

#

initial price of an item is when you set t=0 right?

#

📎 unknown.png

willow bear Oct 12, 2019, 3:20 AM

#

initial

stuck lark Oct 12, 2019, 3:20 AM

#

the word "initial" does indicate at the start of time, so yes, the initial price is presumably when t=0

hollow bluff Oct 12, 2019, 3:21 AM

#

ez

alpine cove Oct 12, 2019, 2:27 PM

#

📎 JPEG_20191012_195615.jpg

#

Cant get the question. Ex.5

willow bear Oct 12, 2019, 2:30 PM

#

$\bigcup_{i=1}^{30} A_i$

obsidian monolithBOT Oct 12, 2019, 2:30 PM

#

Ann:

📎 183668144404037632.png

willow bear Oct 12, 2019, 2:30 PM

#

is this what you wanted to type

alpine cove Oct 12, 2019, 2:30 PM

#

Yes lol

#

I dont get the question

#

Ann do u know how to do this

limber bone Oct 12, 2019, 2:33 PM

#

whats A_i

proud sparrow Oct 12, 2019, 2:34 PM

#

probably something to do with incidence matrices (okay maybe not)

#

It's just a 5 element set

#

Think about the total number of elements in B_1...B_N

alpine cove Oct 12, 2019, 2:35 PM

#

I want to understand the question

proud sparrow Oct 12, 2019, 2:35 PM

#

looks like you are interrupting something

#

oh wait

#

you changed dp

#

no wonder

#

okay tell me what you understand from the question so far

alpine cove Oct 12, 2019, 2:37 PM

#

I get the question

proud sparrow Oct 12, 2019, 2:38 PM

#

okay, so now you know how to solve it?

alpine cove Oct 12, 2019, 2:38 PM

#

Now i dont get the solution

📎 JPEG_20191012_200118.jpg

proud sparrow Oct 12, 2019, 2:39 PM

#

what do you get so far?

#

ah they typoed

alpine cove Oct 12, 2019, 2:40 PM

#

What ?

proud sparrow Oct 12, 2019, 2:40 PM

#

$n(S)=\frac{1}{10}\sum_{i=1}^{30}n(A_i)$

obsidian monolithBOT Oct 12, 2019, 2:40 PM

#

Element118:

📎 104219409991626752.png

alpine cove Oct 12, 2019, 2:40 PM

#

Yws that what they wrote

proud sparrow Oct 12, 2019, 2:41 PM

#

no they didn't write this

#

okay where are you lost?

alpine cove Oct 12, 2019, 2:42 PM

#

I dont get why they divided by 10

proud sparrow Oct 12, 2019, 2:42 PM

#

because each element is in 10 sets

#

by counting the number of elements in Ai, we have overcounted by a factor of 10

alpine cove Oct 12, 2019, 2:43 PM

#

Boi

#

$n(S)=\sum_{i=1}^{30}n(A_i)=A_1 \cup A_2...\cup A_{30}$

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Right?

obsidian monolithBOT Oct 12, 2019, 2:44 PM

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Krishna:

📎 631576009526738944.png

alpine cove Oct 12, 2019, 2:45 PM

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Repeatition of elements are immaterial.

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So i think we must not divide by 10

willow bear Oct 12, 2019, 2:54 PM

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actually, no, you are wrong on that front

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first off

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the second equals sign equates a NUMBER with a SET, which is nonsensical

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@alpine cove

alpine cove Oct 12, 2019, 2:57 PM

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Oh yes

willow bear Oct 12, 2019, 2:58 PM

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so what you wrote is nonsense

alpine cove Oct 12, 2019, 3:01 PM

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Yes.Sorry about that

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$n(S)=\sum_{i=1}^{30}n(A_i)=n(A_1 \cup A2...\cup A{30})$

obsidian monolithBOT Oct 12, 2019, 3:01 PM

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Krishna:

📎 631576009526738944.png

willow bear Oct 12, 2019, 3:03 PM

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now that's no longer nonsensical but just wrong

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n(A U B) != n(A) + n(B) generally

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the first and the last quantities are in fact equal to each other (even if the one on the right is badly typeset) but not to the quantity in the middle

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because yes $S = A_1 \cup A_2 \cup \cdots \cup A_{30}$

obsidian monolithBOT Oct 12, 2019, 3:05 PM

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Ann:

📎 183668144404037632.png

alpine cove Oct 12, 2019, 3:15 PM

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I juusr cant undesrtand the problem aand solution

leaden stratus Oct 12, 2019, 5:00 PM

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How to solve? I divided both terms by 17 and then?

📎 IMG_20191012_185953.jpg

flint vale Oct 12, 2019, 5:01 PM

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Can you convert the roots to exponent form

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As some of it already is

leaden stratus Oct 12, 2019, 5:12 PM

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Uhm... yeah, (2^(x+1))^1/2 @flint vale

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You're right

flint vale Oct 12, 2019, 5:13 PM

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you can remove the outer parenthesis then

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and multiply the half by the the rest of the exponent bc they are both exponents

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do for right side too

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observe the difference in powers between 2 and 4 to make them the same

leaden stratus Oct 12, 2019, 5:16 PM

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No, it will be x < 15 the result

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So we have to exclude this procediment

flint vale Oct 12, 2019, 5:17 PM

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what is the question

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i thought you solve for x

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and compare with the inequality on the side

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ur right tho

leaden stratus Oct 12, 2019, 5:22 PM

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No, sorry. I solved it

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You're right

flint vale Oct 12, 2019, 5:22 PM

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im just curious what the question is

leaden stratus Oct 12, 2019, 5:22 PM

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Find the x

flint vale Oct 12, 2019, 5:22 PM

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yes, you did that

leaden stratus Oct 12, 2019, 5:22 PM

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Yeah. I forgot multipling for 2 the second term

trim fable Oct 12, 2019, 5:23 PM

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guys

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I have a question

leaden stratus Oct 12, 2019, 5:23 PM

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P.S. Thanks @flint vale

flint vale Oct 12, 2019, 5:23 PM

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mp

leaden stratus Oct 12, 2019, 5:23 PM

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@trim fable what's your question

trim fable Oct 12, 2019, 5:24 PM

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how would u do this

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one sec

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📎 unknown.png

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this

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@leaden stratus 😛

leaden stratus Oct 12, 2019, 5:28 PM

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Uhm, I don't think I've done an inequality with more than an inequality symbol

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But I think you have to separate the inequalities

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Then you find the intersection of the inequalities. The first one does not have a solution. I found that the first one gives x < 3 and x > 4 but leads to no solution

trim fable Oct 12, 2019, 5:31 PM

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uh

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how

remote relic Oct 12, 2019, 5:31 PM

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you need to isolate the x

trim fable Oct 12, 2019, 5:31 PM

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how 😅

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lol im good at math but this stuff is just confusing me..

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like im like wow i dont know ahhhh!!

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coz like dont u get

remote relic Oct 12, 2019, 5:32 PM

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so

trim fable Oct 12, 2019, 5:32 PM

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-x-6>x>-x-8?

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unlessssssss

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u bring the x's to the middle?

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then divide 😮

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OH

remote relic Oct 12, 2019, 5:33 PM

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hold on

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im going to try to solve it

regal peak Oct 12, 2019, 5:33 PM

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how do i solve 4 log(2,n) = n
(that's log base 2)

remote relic Oct 12, 2019, 5:36 PM

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@trim fable so you need to seperate the inequality

trim fable Oct 12, 2019, 5:36 PM

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what do u mean by

remote relic Oct 12, 2019, 5:36 PM

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so then you would have x-3 < 3-x and 3-x<x-5

trim fable Oct 12, 2019, 5:37 PM

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oh

remote relic Oct 12, 2019, 5:37 PM

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yes

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then you move all the x to one side

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then you do the same thing for the other equation

trim fable Oct 12, 2019, 5:38 PM

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ok so then u get

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3>x and 4<x

remote relic Oct 12, 2019, 5:38 PM

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yes

trim fable Oct 12, 2019, 5:39 PM

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and for the second one

remote relic Oct 12, 2019, 5:39 PM

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which would make it no solution

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for the second one you would do the same process

trim fable Oct 12, 2019, 5:40 PM

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x>-3 and 4>x

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but why is that no solution?

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how do u know when there isn't a solution

flint river Oct 12, 2019, 5:40 PM

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it is

remote relic Oct 12, 2019, 5:41 PM

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the first one is no solution because you can't have x be less than 3 and also be greater than 4

flint river Oct 12, 2019, 5:41 PM

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-3 < x < 4

trim fable Oct 12, 2019, 5:41 PM

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makes sense

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thanksss guyss

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wait but

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for

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3>x>4

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wont the number line be like this

flint river Oct 12, 2019, 5:43 PM

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uh there's no number below 3 and above 4 at the same time

trim fable Oct 12, 2019, 5:44 PM

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it goes both ways right

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oh so like if x is 2 it cant be less than 3 and greater than 4

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makes sense!!!!!!!

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LOL

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oh

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i have another question

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📎 unknown.png

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equation from # 12 is

#

📎 unknown.png

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so should i just think of f as being x? and same with c?

flint river Oct 12, 2019, 5:47 PM

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yeah solve for F

trim fable Oct 12, 2019, 5:48 PM

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so c would be like x?

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or f is like x?

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i dont get this

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the c and f are confusing me

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@flint river

flint river Oct 12, 2019, 5:49 PM

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it converts from C to F

stuck lark Oct 12, 2019, 5:49 PM

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you're being really unclear when you say "is F like x?"

yeah solve for F

that's all there is to it. isolate F

trim fable Oct 12, 2019, 5:50 PM

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lol

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ok

flint river Oct 12, 2019, 5:50 PM

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its some function which given x yields some y value

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so in this case C is x

trim fable Oct 12, 2019, 5:51 PM

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so like

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(9c/5)+32= F

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so thats all I had to do?

stuck lark Oct 12, 2019, 5:52 PM

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👍🏽

trim fable Oct 12, 2019, 5:52 PM

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ok

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but like

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hows that an inequality?

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the inequality things just confusing me

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can someone just tell me what an inequality means

stuck lark Oct 12, 2019, 5:53 PM

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first off

(9c/5)+32= F
is not an inequality

trim fable Oct 12, 2019, 5:53 PM

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whats an inequality tho

stuck lark Oct 12, 2019, 5:54 PM

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a statement saying that two values are not equal

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$a<b$ tells us a is less than b

obsidian monolithBOT Oct 12, 2019, 5:54 PM

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RokettoJanpu:

📎 150414892225134592.png

willow bear Oct 12, 2019, 5:55 PM

#

📎 unknown.png

stuck lark Oct 12, 2019, 5:55 PM

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~~isn't that more effort than linking lmgtfy?~~

willow bear Oct 12, 2019, 5:55 PM

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yes it is

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but a lmgtfy link doesn't have the same amount of sass

stuck lark Oct 12, 2019, 5:56 PM

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~~you are right~~

trim fable Oct 12, 2019, 5:56 PM

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uh what

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lol

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ok

stuck lark Oct 12, 2019, 5:57 PM

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look, first read what i said about what a<b means. if you're still confused on inequalities, then look through your past algebra material on that stuff, or google it as suggested

trim fable Oct 12, 2019, 5:58 PM

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ok im not confused anymore

pseudo sonnet Oct 12, 2019, 5:59 PM

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Determine which quadrant the terminal side of the angle -16.92lies in.

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what is -16.92?

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the angle or length of terminal side

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im confused af

stuck lark Oct 12, 2019, 5:59 PM

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the angle

pseudo sonnet Oct 12, 2019, 5:59 PM

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oh

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im assuming -16.92 is radians then?

stuck lark Oct 12, 2019, 5:59 PM

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i'd assume so too

pseudo sonnet Oct 12, 2019, 6:03 PM

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how do I convert -16.92 to degrees if I cant use 180/pie

clear glade Oct 12, 2019, 6:14 PM

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how do i find phase shift of a graph?

pseudo sonnet Oct 12, 2019, 6:15 PM

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https://i.imgur.com/Bx7XnGu.png

Imgur

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is this how I would do it?

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then keep adding 360 till i get to coterminal

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its suppose to be -16.92

stuck lark Oct 12, 2019, 6:17 PM

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are you not confident in traveling around the unit circle using radians?

pseudo sonnet Oct 12, 2019, 6:17 PM

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well the problem is

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im use to seeing x/Pie radians

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this is just -16.92

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would I add 2pie

stuck lark Oct 12, 2019, 6:17 PM

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what's an approximate decimal representation of pi?

pseudo sonnet Oct 12, 2019, 6:17 PM

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till its positive

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3.14

stuck lark Oct 12, 2019, 6:17 PM

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how about 2pi?

pseudo sonnet Oct 12, 2019, 6:18 PM

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6.28

stuck lark Oct 12, 2019, 6:18 PM

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now run with that

pseudo sonnet Oct 12, 2019, 6:18 PM

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but i want an exact answer

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not approximation

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wait so

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do I add 2pi to -16.92

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or do I add 6.28 to -16.92

stuck lark Oct 12, 2019, 6:18 PM

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getting a decimal in converting rad to deg will never be exact since the conversion involves pi

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then keep adding 360 till i get to coterminal
what's the equivalent action when working in radians?

pseudo sonnet Oct 12, 2019, 6:20 PM

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2pie

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but since the original question isnt in pie radians

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do I just approximate 2pie to 6.28

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then add that to -16.92

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till i get to positive coterminal

stuck lark Oct 12, 2019, 6:21 PM

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sounds fine

velvet elm Oct 12, 2019, 6:34 PM

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I am stuck on this problem.

📎 unknown.png

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I use change of base and get log(b,2.8) over log(b,5b), (sorry I don't know latex)

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so the denom = B+1, but i don't know what to do with the logb2.8

willow bear Oct 12, 2019, 6:36 PM

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$\frac{\log_b(2.8)}{\log_b(5b)} = \frac{\log_b(2.8)}{B+1}$

obsidian monolithBOT Oct 12, 2019, 6:36 PM

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Ann:

📎 183668144404037632.png

willow bear Oct 12, 2019, 6:36 PM

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so this is what you have to far, right?

velvet elm Oct 12, 2019, 6:36 PM

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Yes

willow bear Oct 12, 2019, 6:36 PM

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$2.8 = \frac{14}{5}$

obsidian monolithBOT Oct 12, 2019, 6:36 PM

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Ann:

📎 183668144404037632.png

velvet elm Oct 12, 2019, 6:37 PM

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Ohh...

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Hmm let me think where to take that, but that helps! thanks!

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(A+C-B)/B+1

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Thank you! @willow bear

willow bear Oct 12, 2019, 6:42 PM

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the denom needs parentheses around it too but yes

velvet elm Oct 12, 2019, 6:44 PM

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You're right, I wrote it into my online homework correctly, just not here

pseudo sonnet Oct 12, 2019, 6:46 PM

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📎 image0.jpg

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@stuck lark is my work right

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the equal signs should be approximations

stuck lark Oct 12, 2019, 6:48 PM

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close enough 👍🏽

pseudo sonnet Oct 12, 2019, 6:54 PM

#

https://i.imgur.com/ITdHn9x.png

Imgur

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📎 image0.jpg

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did i draw this right lol

stuck lark Oct 12, 2019, 6:56 PM

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looks fine

pseudo sonnet Oct 12, 2019, 7:04 PM

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https://i.imgur.com/Uf7cJOx.png

Imgur

#

📎 image0.jpg

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is my drawing and equation set up correctly

willow bear Oct 12, 2019, 7:05 PM

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seems so

pseudo sonnet Oct 12, 2019, 7:30 PM

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📎 image0.jpg

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how come for e)

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$sin(5\pi/3) = -\sqrt{3}/2$

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idk how to put pi and square root lel

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but my answer was positive

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and the correct answer is negative

gentle vigil Oct 12, 2019, 7:32 PM

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How was your answer positive?

pseudo sonnet Oct 12, 2019, 7:34 PM

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look at my triangle

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i drew it out

willow bear Oct 12, 2019, 7:34 PM

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ew bad tex

pseudo sonnet Oct 12, 2019, 7:34 PM

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ye lol

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idk how to make pi and square root

willow bear Oct 12, 2019, 7:34 PM

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$\pi$

obsidian monolithBOT Oct 12, 2019, 7:34 PM

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Ann:

📎 183668144404037632.png

willow bear Oct 12, 2019, 7:34 PM

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$\sqrt{123}$

obsidian monolithBOT Oct 12, 2019, 7:34 PM

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Ann:

📎 183668144404037632.png

gentle vigil Oct 12, 2019, 7:35 PM

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Is that correct?

obsidian monolithBOT Oct 12, 2019, 7:35 PM

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Vici:

📎 312632830230396940.png

pseudo sonnet Oct 12, 2019, 7:35 PM

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yeah

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but i got a positive answer

gentle vigil Oct 12, 2019, 7:37 PM

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$\sin{5\pi/3} =\sin{(2\pi-\pi/3)}$

obsidian monolithBOT Oct 12, 2019, 7:37 PM

#

oscillatingEquilibrium:

📎 578010204726231090.png

pseudo sonnet Oct 12, 2019, 7:37 PM

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yeah i googled it and saw that

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but whats wrong with the way i did it?

gentle vigil Oct 12, 2019, 7:38 PM

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I didn't understand how you did it

pseudo sonnet Oct 12, 2019, 7:38 PM

#

📎 image0.jpg

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$5\pi/3 - 3\pi/3$

gentle vigil Oct 12, 2019, 7:39 PM

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$\sin{(x-\pi)} = -\sin{x}$

obsidian monolithBOT Oct 12, 2019, 7:39 PM

#

Vici:

📎 312632830230396940.png

stuck lark Oct 12, 2019, 7:39 PM

#

5pi/3 is not coterminal with 2pi/3

obsidian monolithBOT Oct 12, 2019, 7:40 PM

#

oscillatingEquilibrium:

📎 578010204726231090.png

pseudo sonnet Oct 12, 2019, 7:40 PM

#

my reality has been shattered

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im lost

stuck lark Oct 12, 2019, 7:40 PM

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previously, how did you find the coterminal of some big ugly angle?

pseudo sonnet Oct 12, 2019, 7:41 PM

#

📎 image0.jpg

#

i did the same thing for those 2 problems at the bottom

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and it worked

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lol

stuck lark Oct 12, 2019, 7:42 PM

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how did you find the coterminal of some big ugly angle?

gentle vigil Oct 12, 2019, 7:42 PM

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For sin, cos, sec, csc, it's better to add or subtract multiples of $2\pi$, not $\pi$

obsidian monolithBOT Oct 12, 2019, 7:42 PM

#

oscillatingEquilibrium:

📎 578010204726231090.png

gentle vigil Oct 12, 2019, 7:43 PM

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It won't change sign of the functins

hoary valley Oct 12, 2019, 7:44 PM

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What's the next step in solving this problem ? I want to get rid of one of the t's to solve for the other T...

📎 Screenshot_122.png

stuck lark Oct 12, 2019, 7:44 PM

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that can be rewritten as a quadratic equation

gentle vigil Oct 12, 2019, 7:46 PM

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@hoary valley seems like a physics problem 😂

hoary valley Oct 12, 2019, 7:46 PM

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It is, but I'm struggling with the math part of it...

pseudo sonnet Oct 12, 2019, 7:46 PM

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smh

stuck lark Oct 12, 2019, 7:46 PM

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do you know the general form of a quadratic equation?

hoary valley Oct 12, 2019, 7:47 PM

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yes x^2 + x + number = 0 @stuck lark

gentle vigil Oct 12, 2019, 7:47 PM

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$t = \frac{-b ± \sqrt{\Delta}}{2a}$

obsidian monolithBOT Oct 12, 2019, 7:47 PM

#

oscillatingEquilibrium:

📎 578010204726231090.png

hoary valley Oct 12, 2019, 7:47 PM

#

something like that

gentle vigil Oct 12, 2019, 7:47 PM

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Are you familiar with this?

stuck lark Oct 12, 2019, 7:48 PM

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@hoary valley not quite

hoary valley Oct 12, 2019, 7:48 PM

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@gentle vigil No man

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@gentle vigil what's b ?

stuck lark Oct 12, 2019, 7:48 PM

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$ax^2+bx+c=0 \\ a \neq 0 \ a,b,c \in \bR$

obsidian monolithBOT Oct 12, 2019, 7:48 PM

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RokettoJanpu:

$ax^2+bx+c=0 \\\\ a \neq 0 \\ a,b,c \in \bR$

📎 150414892225134592.png

hoary valley Oct 12, 2019, 7:49 PM

#

Wait I think I get it @stuck lark I will get 2 answers one of them will be correct

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I will try solving

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@stuck lark Wait I'm used to solve x^2 but this x^2 has a -4.9 next to it

stuck lark Oct 12, 2019, 7:51 PM

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how would you deal with that?