#help-39

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brisk nacelle
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Yes

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So its right?

cloud zephyr
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because 15β‰ 30

brisk nacelle
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I wrote no solution

cloud zephyr
brisk nacelle
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Okay

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brisk nacelle
pearl pondBOT
brisk nacelle
#

Is this right?

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???

pearl pondBOT
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plucky cove
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I need help figuring out each one

pearl pondBOT
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Please don't occupy multiple help channels.

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The purpose of this server is to help you learn, not to hand out answers. Do not ask someone to give you the answer directly.

plucky cove
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I need help solving each problem

pearl pondBOT
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gusty prism
pearl pondBOT
gusty prism
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How do u know when to use these equations really

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They said it is all for constant acceleration but didn't rlly say when to use which

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I guess if i do practice ill realize but

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For the constant acceleration motion

sharp vigil
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all of them have a subset of all the variables, so you pick one based on which ones you have and which one you need to solve for

pearl pondBOT
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gusty prism
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perfect

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thanks

pearl pondBOT
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toxic tulip
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Hello I need finding the mistake in a proof

iron stream
toxic tulip
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Let 𝐴, 𝐡 βŠ‚ 𝐢. If 𝑝 is a limit point of 𝐴βˆͺ𝐡, then 𝑝 is a limit point of 𝐴or 𝐡. Proof Suppose p is a limit point of A union B. If I is an open interval containing p, then by definition of limit point, I intersect (A union B) minus {p} is nonempty. Therefore, it contains a point x. Then x is in I and x is in A union B, and x is not equal to p. Since x is in A union B, either x is in A or x is in B. In case 1, x is in A. Then x is in I intersect A minus {p}, so I intersect A minus {p} is not empty. Therefore, p is a limit point of A. Similarly, if x is in B, p is a limit point of B.

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and yeah I made this account in Middle School it was dark times

pearl pondBOT
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@toxic tulip Has your question been resolved?

tropic saddle
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for each interval I you get a different x

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sometimes that x may be in A and sometimes it may be in B

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but it would always need to be in the same one

toxic tulip
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could you maybe elaborate a little bit

tropic saddle
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say p was a limit point of A. then x would always have to be in A

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but you have only shown that it is sometimes in A or sometimes in B

toxic tulip
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I see what your saying since x is in A union B it could be in either A or B regardless of where the limit point is

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How could this be accounted for in the proof?

tropic saddle
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tbh not sure right now

toxic tulip
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I think I have enough to go off now thank you

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.clsoe

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brazen swift
pearl pondBOT
brazen swift
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The question asks to prove this identity

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i mean its just cos2x = cos^2(x)-sin^2(x)

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but that seems too easy

acoustic path
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that's correct

brazen swift
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i mean if i just use that it gets me the answer immediately but that seems too easy

acoustic path
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but it is valid proof

brazen swift
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im not sure if they mean without using that identity

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like its not said anywhere

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but its too simple

acoustic path
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cosine double angle formula is a staple identity that should be allowed to be used aside from (maybe) first encounter

opaque lantern
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man i hate trigonometry

acoustic path
brazen swift
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butl ike

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the question before

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number 5

opaque lantern
brazen swift
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says
prove these identities of cosine with a double angle

brazen swift
opaque lantern
brazen swift
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so i assume i dont need to repeat ?

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also the case at question 6

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i just apply it and thats it

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πŸ€”

opaque lantern
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yupp u gotta apply the same identity

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sin2(3x) this time

brazen swift
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yeah im just overthinking it

opaque lantern
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try it

brazen swift
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thinking its supposed to be harder

opaque lantern
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nuh

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take it ez

brazen swift
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ig

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alr

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thanks

opaque lantern
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yw

brazen swift
opaque lantern
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bro idk abt this one 😭

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sorry abt tht i suck at trigono

brazen swift
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@acoustic pathany help?

opaque lantern
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thanks for understanding

brazen swift
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the thought is what counts

opaque lantern
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have a good day!

brazen swift
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u2

acoustic path
brazen swift
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didnt notice it

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i was looking at the right side

acoustic path
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ok

acoustic path
noble abyss
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can any1 help

brazen swift
acoustic path
brazen swift
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1-cos^2(0.5a) + sin^2(0.5a) / 2

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after using the cos(2a) identity

acoustic path
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that is not in terms of sin(a/2)

brazen swift
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Oh

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i thought

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opening the

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-cos(a)

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is what you meant

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but

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makes more sense

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give me a min

acoustic path
brazen swift
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huh

acoustic path
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but the expression (1-cos^2(0.5a) + sin^2(0.5a)) / 2 is not in terms of sin(a/2)

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it is in terms of sin(a/2) and cos(a/2)

brazen swift
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in other words?

acoustic path
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look at what u did in q 5

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use the identity at the very right

brazen swift
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πŸ‘

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Oh

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howd you know which one to pick?

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Assuming because it's the only one to not include cos?

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@acoustic path?

pearl pondBOT
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@brazen swift Has your question been resolved?

pearl pondBOT
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midnight haven
pearl pondBOT
midnight haven
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first time seeing this function can someone nice pls explain wth is going

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on

muted inlet
midnight haven
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yeah but first time seeing this functions graph

muted inlet
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ex: if x=-2 (plug into top) 5(-2)+1 =-9. x=0 0^2 -5 =-5

midnight haven
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not really but this specific graph

muted inlet
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ok It's spilt into two graphs

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one graph is just 5x+1 which is a line

midnight haven
muted inlet
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k. Just look at the graph and see when the Y value is going down and then see what x values coordinate with the range that the y value is decreasing

midnight haven
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i think it goes down from -4? but idk

muted inlet
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yes that is the y value when the graph starts to decrease, but you always want to look at the x values because there could be many y=-4 on the graph, but there is only one x=-1

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so the graph starts the decrease at x=-1

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When does it end the decrease?

midnight haven
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dont think it ever does but thats my guess

muted inlet
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when the graph is going down it is decreasing and when it goes up it increases. when the y value goes up it increases and when it goes down it decreases

midnight haven
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okay

muted inlet
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make sure you are always looking left to right when seeing if its increasing or decreasing

midnight haven
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so u said it decreaces at (1-,-4)?

muted inlet
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yes that is when it starts to decrease

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but then it starts to increase again

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when does it stop decreasing?

midnight haven
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the same points?

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like (-1,-4)

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how do i answer it

muted inlet
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just pretend your drawing the graph from left to right

midnight haven
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theres no option for (-1,-4)

muted inlet
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when you pensil starts going down it is decreasing and when it goes up your increasing

midnight haven
muted inlet
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(-1,-4) and (0,-5) is in (x,y) it wants you to answer from a range. (x-x) because graphs often cross the same y value more then once but never the same x value

midnight haven
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oh

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they should've wrote that

muted inlet
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Yeah, but they dont sadcat

midnight haven
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so is the 2nd option correct

muted inlet
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no

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You said that it starts decreasing at (-1,-4) and stops decreasing at (0,-5) but it only wants a range of X VALUES

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so you dont care about the y values and just put the two x values together

midnight haven
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oh ok

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so 3rd option

muted inlet
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yep

midnight haven
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?

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okay

#

tysm <33

muted inlet
#

ofc

midnight haven
#

.close

pearl pondBOT
#
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gloomy kraken
#

is this correct?

pearl pondBOT
gloomy kraken
dawn sand
#

looks good to me

gloomy kraken
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sorry i think theres supposed to be an 8 in place of 16

gloomy kraken
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cause k was 12

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j-4 = k, 12-4

dawn sand
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k=12 implies j=12+4=16

dawn sand
gloomy kraken
#

im slow today

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thanks again

dawn sand
#

mondays amirite

gloomy kraken
#

.close

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orchid cobalt
pearl pondBOT
orchid cobalt
#

process so far

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i rlly dont know what im doing

old marsh
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ok well u showed some good logic

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but just start over

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keep it in radical form

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rewrite sqrt(15) as a product of radicals

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what do u get

orchid cobalt
orchid cobalt
old marsh
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$\frac 1{\sqrt 3} - \frac {2\sqrt 3}{\sqrt 5 \cdot \sqrt 3}$

jolly parrotBOT
old marsh
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ok now what

orchid cobalt
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guys im sorry im kind slow at this

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does the square root of three on the numerator and denominator cancel out-?

old marsh
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we can do that, but i suggest another path

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how about you make common denominators

orchid cobalt
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oh how would i do that?

old marsh
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$\frac ab - \frac cd$

jolly parrotBOT
old marsh
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how would u make common denominators here

orchid cobalt
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ad/bd - cb/db

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?

old marsh
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but those arent common denominators

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how about this

orchid cobalt
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oh damn ure right

old marsh
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$\frac 12 - \frac 23$

jolly parrotBOT
old marsh
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how would u make common denominators for this

orchid cobalt
#

id just make them both 6

old marsh
#

ok but howd u get that

orchid cobalt
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by multiplying 1/2 by 3/3

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and 2/3 by 2/2

old marsh
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exactly

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and how did u get 3/3

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and 2/2

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ur on the right track, just tell me ur reasoning

orchid cobalt
#

would i do this-?

orchid cobalt
old marsh
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yes lcm

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,rotate

jolly parrotBOT
old marsh
#

ok well yes, that looks correct, but theres a better way

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mult left fraction by sqrt5 / sqrt5

orchid cobalt
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would they cancel out?

old marsh
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no we dont want to cancel anything out yet

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$\frac 1{\sqrt 3} - \frac {2\sqrt 3}{\sqrt 5 \cdot \sqrt 3}$

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back to this

jolly parrotBOT
old marsh
#

see how the denominator of the right fraction is sqrt 3 * sqrt 5

orchid cobalt
#

yes

old marsh
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mutliply the left fraction by sqrt5 / sqrt 5

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so u will get sqrt3 * sqrt 5 in both denominators

orchid cobalt
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ohhh!!

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ok ok i got it

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so after this part

old marsh
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$\frac {\sqrt 5}{\sqrt 5 \cdot \sqrt 3} - \frac {2\sqrt 3}{\sqrt 5 \cdot \sqrt 3}$

jolly parrotBOT
orchid cobalt
#

how do we simplify it further?

old marsh
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now what do we do after we get common denominators

orchid cobalt
#

subtract?

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but like im not rlly sure how to subtract ;-;

old marsh
#

$\frac ac - \frac bc = \frac {a-b}c$

jolly parrotBOT
old marsh
#

thats all theres to it

orchid cobalt
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but how do you subtract roots-?

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im sorry for wasting so much of ur time

old marsh
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nah ur good dw

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so yes that is correct

orchid cobalt
#

is this the final answer?

orchid cobalt
old marsh
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not yet, we have to still rationalize

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do u know what that is

orchid cobalt
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im sorry but no ;-;

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ive been kinda absent from class for a short while..

old marsh
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meaning, we cant have any radicals in the denominator

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how can we get rid of that sqrt(15) in the denominator

orchid cobalt
#

oh could the square root of 5 cancel out and the square root of 3 cancel out?

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btw this is the answer ;-;

old marsh
#

so we have

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$\frac {\sqrt 5 - 2\sqrt 3}{\sqrt {15}}$

jolly parrotBOT
orchid cobalt
#

mhmm

old marsh
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now to rationalize

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we have to multiply the numerator and the denominator by sqrt(15)

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lmk what u get when doing that

orchid cobalt
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i got (5 -6)/15 ;-;

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how do they still have squares?

old marsh
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ok so ur denominator is correct, but we have to distribute the sqrt(15) to the numerator

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$\frac {\sqrt{15} (\sqrt 5 - 2\sqrt 3)}{15}$

orchid cobalt
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oh ok

old marsh
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can u distribute that

jolly parrotBOT
old marsh
#

when u distribute u get

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$\frac {\sqrt{15} \cdot \sqrt 5 - \sqrt {15} \cdot 2\sqrt 3}{15}$

orchid cobalt
jolly parrotBOT
orchid cobalt
#

is this it-?

old marsh
#

good

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and theres ur numerator

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and we have 15 as the denominator

orchid cobalt
#

OMG TYSM!!

old marsh
#

so theres ur answer

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np

orchid cobalt
#

youre a hero sent from the heavens

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ok ok ill quickly take notes from everything!!

old marsh
#

πŸ‘

#

cya

orchid cobalt
#

.close

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deep thistle
#

How does the top group of cells simplify to A'?

plush bramble
#

What are A and Abar

cosmic charm
#

its a k-map

feral leaf
deep thistle
#

I don't think I you more context for this tbh

deep thistle
feral leaf
#

Not always, it depends on the number of terms

deep thistle
#

2 terms

feral leaf
#

Then yes

deep thistle
#

If it were this, it would be B'

#

?

feral leaf
#

Yes

deep thistle
#

ahh gotcha!

#

okay thanks!

#

.close

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opaque hearth
#

How could you find two vectors u and v given their cross product?

west sapphire
#

there's no unique answer

sharp vigil
#

that wouldn't have a unique answer. for example
i x j = k
j x (-i) = k

west sapphire
#

more generally, take i and j, and rotate them both by the same angle (any angle), cross product is still k

pearl pondBOT
#

@opaque hearth Has your question been resolved?

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glad glen
#

I'm having trouble with 31. i dont know how to even start the equation

versed ledge
glad glen
#

ty

#

.close

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outer hare
#

Hey, can anyone explain what this k represents:

outer hare
#

here is the 2.5 they are referencing:

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im having trouble understanding how to find a max bound

pearl pondBOT
#

@outer hare Has your question been resolved?

merry carbon
outer hare
#

So for this case the max will always be 1 no

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Like taking a look at the theorem before it

merry carbon
merry carbon
outer hare
#

Yup

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So is k just the abs value of the derivative at p_0

merry carbon
#

What you want is that there's some constant, which is less than 1, such that the absolute value of the derivative is less than that (which is stronger than saying you want |g'(x)| < 1)

merry carbon
jolly parrotBOT
#

@merry carbon

outer hare
#

Hmm

merry carbon
#

It needn't be its maximum at the point p0 you've chosen, in fact, for the example of e^x in [-2, -1], any point in that interval can be chosen as p0 (but the max happens at -1)

outer hare
#

Ok wait I’m not looking at it rn but I’ll get a paper and try to understand it when I get back

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But from what I get, k is just the max value of the derivative within the interval

merry carbon
#

Yep, that's pretty much what you kind of want, that k is the max (or sup) of the absolute value of the derivative

#

But as long as that k is strictly less than 1...

outer hare
#

Because of the rule of convergence states before

#

.close

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naive hemlock
#

Need help with this question
Explanation would be appreciated

pearl pondBOT
#

@naive hemlock Has your question been resolved?

terse bloom
#

the identity function satisfies all three of the restraints and has a derivative of 1 at x = 0

west sapphire
#

i suspect it should have said f(0) = 0

naive hemlock
#

Idk

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That's why I came

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@west sapphire

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@terse bloom

west sapphire
#

yea?

naive hemlock
#

Can u help

west sapphire
#

as noted, the problem is incorrect

naive hemlock
#

Like I did not get what you all were speaking above

west sapphire
#

f(x) = x is a counterexample

naive hemlock
naive hemlock
#

f(0)=0

west sapphire
#

well where did you find the problem?

naive hemlock
#

In the assignment

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πŸ’€β˜ οΈ oof

west sapphire
#

is that a screenshot of the assignment, or did you write your own version

naive hemlock
#

Ss

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Why would I write my own version

west sapphire
#

yea i would confirm with whoever wrote it, what did they intend

naive hemlock
#

Yes tell

west sapphire
naive hemlock
#

Yea ik

#

Back then when I used to remain active πŸ’€

west sapphire
#

anyway i am pretty sure they meant f(0) = 0, not f'(0) = 0

naive hemlock
#

Ok so now for f(0)=0

west sapphire
#

and if that's the case, you can prove it pretty easily using the mean value theorem

naive hemlock
#

Yes

#

We should do mean value

west sapphire
#

yep

naive hemlock
#

But can I be clarified

#

Like I apply lmvt

#

So I get

#

f'(c)=1

west sapphire
#

you applied it to which interval?

#

[-a, a]?

naive hemlock
#

[-a,a]

#

Should I apply till 0

west sapphire
#

yea that's true but it doesn't help much

#

instead try [-a,0] and [a,0]

naive hemlock
#

Ok applying

#

Oh

west sapphire
#

assume for contradiction that f(0) is not 0

naive hemlock
#

Oh

#

I get it

#

When I apply for first intervap

west sapphire
#

you should find that the slope has to exceed 1 in abs val in one of the two intervals

naive hemlock
#

Interval*

#

That's fine

#

But

#

Like wait let me send pic

#

Of my work

west sapphire
#

ok

naive hemlock
#

Here

#

Don't go pls

west sapphire
#

no start by assuming that f(0) is not 0

#

so there are two possibilities

#

either f(0) > 0 or f(0) < 0

naive hemlock
#

Wait

west sapphire
#

if f(0) > 0, then do the MVT on [-a,0]

naive hemlock
#

U are right how did I put f(0)=0

#

πŸ’€ tf

west sapphire
#

otherwise do it on [0,a]

#

(this is assuming a > 0)

#

btw, they should have stipulated a != 0 in any case, otherwise it's not true

naive hemlock
#

See

#

I got

#

f'(c)=[f(0)-a]/a in [-a,0] and f'(d)=[a-f(0)]/a in [0,a]

#

Now ?

#

Fr my mind is blocked today

west sapphire
#

yea so if f(0) > 0 then in the interval [-a,0] you have:
[f(0) - (-a)] / (0 - (-a)) = [f(0) + a] / a = f(0)/a + 1 > 1

#

and so there has to be a c with f'(c) > 1

#

contradiction

#

argue similarly if f(0) < 0

naive hemlock
#

Bro

#

Do we have any simple solution

west sapphire
#

isn't that pretty simple?

#

it's like 3 lines

naive hemlock
#

Cz I don't think the teacher has told us about assumption in any of the practice problems

west sapphire
#

which assumption?

naive hemlock
#

I need to frame and explain

#

Is there not any method

#

Which uses the mean value theorems

#

And gives somewhat direct result?

west sapphire
#

that's the simplest argument i can think of

naive hemlock
#

Bro you are right?

#

But is there?

#

Pls try

#

This question's solution has to go in the assignment In a well explained wau

#

Way*

west sapphire
#

i already gave you a nearly complete argument haha

#

i'm not gonna write it out in camera-ready form

naive hemlock
#

Oh

#

Oof

#

Bro I don't need the solution

#

I need some other simple way

#

Which directly proves f(0)=0

#

Without taking f(0)>0 and f(0)<0 in the beginning

#

@west sapphire

pearl pondBOT
#

@naive hemlock Has your question been resolved?

pearl pondBOT
#

@naive hemlock Has your question been resolved?

naive hemlock
#

<@&286206848099549185>

pearl pondBOT
#

@naive hemlock Has your question been resolved?

naive hemlock
#

@west sapphire thanks got it

#

@west sapphire

#

Can I be helped with these two questions also

#

Aah

#

Fr

#

<@&286206848099549185>

#

Anyone?

rough forge
naive hemlock
#

No

#

What

#

This is

#

Theorems bro

#

Bacc do you have any idea

#

How to do

rough forge
#

No

#

It's like the same like last time lol

#

You may also ask in calculus

#

most of the time the pros are there

plucky python
#

if f(x) = 1 - x^2, a=-1, b=1

naive hemlock
#

Idk

#

Honestly

#

Idk

plucky python
#

then it's twice differentiable with f(a) = f(b) = 0 and f(c) > 0 for all c in (a,b)

naive hemlock
#

I am tired

#

This question has troubled me too much now

plucky python
#

but f''(x) = -2 so the conclusion is not true

naive hemlock
#

My assignment is due tmrw

#

That's why I came here now at last to understand

#

This

#

One

#

Question

plucky python
naive hemlock
#

Can u try for once

plucky python
#

wdym?

naive hemlock
#

No like

#

Can it be true for any case

plucky python
#

i mean like you can create a scenario in which it is true

plucky python
naive hemlock
#

Ik

#

Honestly

#

Speaking

#

Can u see the 14th one

#

Once

#

I will send the pic again wait

plucky python
#

i've had a look at it

#

still thinking but like that's hard

naive hemlock
#

In 14th one

#

If u remove the right term from consideration

#

It becomes cmvt

#

Cauchy's mean value theorem

plucky python
#

yes

naive hemlock
#

But then we don't have g'(x) not equal to 0

#

Its given g(x) not equal to 0

#

The assignment has questions that are too ambiguous

#

Can u suggest what should I do now

#

For the 15th one

#

I need to write an answer for it

#

Should I modify the question

plucky python
naive hemlock
plucky python
#

and say that the problem seems to be wrong

plucky python
naive hemlock
#

Yes

#

All 15

plucky python
#

bruh

naive hemlock
#

But I am troubled with this one

#

Two above troubled me too

#

But I cross checked and the questions were wrong

#

So I modified them

#

But 14. And 15. Trouble me

#

Too much

plucky python
naive hemlock
#

Me too

plucky python
#

also have u tried posting it to real and complex analysis?

naive hemlock
#

Should I?

plucky python
naive hemlock
#

Isn't it supposed to be calculus?

plucky python
#

for 14

naive hemlock
#

Yes

#

Tell me

#

Asap

plucky python
#

try cauchy MVT on f and 1/g

naive hemlock
#

Aah

plucky python
#

i think that works

naive hemlock
#

I m done

#

Fr I can't unsee it now

plucky python
#

cus G(a)G(b)/(G(b)-G(a) is 1/(1/G(a) - G(b)) or whatever

naive hemlock
#

But

#

Wait

#

Its surreal

#

Yes it works

#

That's why they gave g(x) not zero for any x

#

Thanks bro u saved me

plucky python
#

nw lol

naive hemlock
#

Wait now I need to get other s checked.too

plucky python
#

also it seems a little strict that you have to submit for every problem

naive hemlock
#

pls wait

#

I need to submit soln for each question in assignment file

plucky python
#

like at my uni we don't need to submit all the problems, as long as we've given like a proper attempt at the sheet

naive hemlock
#

And they will be evaluated

#

Under iA

#

Internal assessment

#

Along with if the professor wants

#

A viva

#

Sort of

#

πŸ’€

#

Wait see this

#

Wait let me send specific one

#

Check for 11

#

Is it correct

#

cz I have assumed that it should be f(0)=0

#

And done it

#

@plucky python

plucky python
#

if f(0) > 0 then you get a contradiction by applying MVT to -a and 0

#

if f(0) < 0 then you get a contradiction by applying MVT to 0 and a

#

UK

#

i study at cambridge uni

naive hemlock
#

I have done

#

F(0)=0

#

Can u check will it be f'(0)=0 only

plucky python
#

but technically if you prove that you also prove f'(0) = 0 lol?

naive hemlock
#

What

#

What

#

What

#

@plucky python

#

I will make myself clear

#

I assumed the question will be f(0)=0 and proved it

#

Will in the question it will remain f'(0)=0

#

Only

plucky python
#

oh right i understand what ur asking now

#

i think the question is meant to be prove f'(0) = 0

plucky python
naive hemlock
#

Ok

plucky python
#

so f'(0) = 0

naive hemlock
#

Once more pls

#

Bro but don't you think this prove f(0)=0

#

?

plucky python
#

this gives you f(x) = x for all x in that interval

#

i think the question basically wants you to just show that f has to be linear

#

and it's asking you to do that by showing f'(0) = 0

#

oh wait ignore me i'm dumb

#

the derivative of a linear function isn't 0 mb lol

plucky python
naive hemlock
#

@plucky python

#

Bro one doubt

#

In the 14.

rough forge
#

Your assignment is crazy

plucky python
plucky python
#

if so i feel like that's an issue that they sort-of brushed to the side

naive hemlock
#

No

#

I mean

#

Will there be no problem

#

Using 1/G(x)

#

Imma come

#

I need to make a cover

#

Wait

plucky python
naive hemlock
#

Okok

#

No it does not say g'(c)=0

#

Ya wait

#

You are correct

#

They have not given that g'(c) is not zero

pearl pondBOT
#

@naive hemlock Has your question been resolved?

pearl pondBOT
#
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β€’ Show your work, and if possible, explain where you are stuck.
β€’ After 15 minutes, feel free to ping <@&286206848099549185>.
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β€’ Be polite and have a nice day!

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abstract halo
pearl pondBOT
abstract halo
#

so in this situation, finding the characteristic equation would be 10r^2+20r+6260=100 -> r^2+2r+626=10

#

solving that gets me r = -1 +- 25i

#

for my homogeneous equation, would it be q(t) or I(t)?

#

I'm thinking its q(t) but the hint makes me go towards I(t), but I'm not sure how I(t) makes sense. If I go the q(t) route, I get C1= 0, C2=0

merry carbon
jolly parrotBOT
#

@merry carbon

abstract halo
#

yes

merry carbon
#

In which case, the solutions you find would be for q

abstract halo
#

I'm getting my constants as C1 = 0 and C2 = 0, in which case q(t) just = 0

#

do I have to multiply them by some power of t?

terse tide
#

the differential equation gotta be in terms of i, not q

#

after you differentiate, put dq/dt = i

merry carbon
terse tide
#

dont change everything to q, why

abstract halo
#

hmm I'm not sure if I'm explaining well

#

I'll send a picture of my work

merry carbon
terse tide
#

no no :p

#

when he differentiates, hell get the dq/dt (3rd term)

#

he replaces that with i(t) and there you go

#

i'' + 2 i' + 626 i = 0

abstract halo
#

hmmm I seee

abstract halo
#

and i' and i terms

terse tide
#

yes, i' will become i'', and i will become i'

abstract halo
#

thank you guys!!!

terse tide
#

and q will become dq/dt, which is i

abstract halo
#

.close

pearl pondBOT
#
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pearl pondBOT
#
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β€’ Show your work, and if possible, explain where you are stuck.
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β€’ Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

dusk otter
#

Need some assistance with this natural deduction proof. I have been playing around with it, but unsure of the next step I can take. I have attached the rules that I can use.

pearl pondBOT
#

@dusk otter Has your question been resolved?

pearl pondBOT
#

@dusk otter Has your question been resolved?

pearl pondBOT
#
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β€’ Ask your math question in a clear, concise manner.
β€’ Show your work, and if possible, explain where you are stuck.
β€’ After 15 minutes, feel free to ping <@&286206848099549185>.
β€’ Type the command .close to free the channel when you're done.
β€’ Be polite and have a nice day!

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slim rock
#

i dont get how im supposed to solve this

pearl pondBOT
slim rock
#

this is all of the instructions

#

do i not just have to get the x value of that midpoint?

vestal tapir
#

yeah, root is x

#

but you need to improve the guess 10 times

slim rock
#

right i give the value thats literally on top of that mid point

#

i just dont understand what its asking in that first part

vestal tapir
#

the midpoint is closer to 1.512 in that picture

#

it's the average of the 2 side xs

slim rock
#

right the 2 sides are movable

#

the mid one is stationary

vestal tapir
#

ok that doesn't make sense, y=0 is not even visible

#

you should zoom out and move the sides so they are around 0

slim rock
#

thats what im confused about

#

it doesnt zoom out

vestal tapir
#

yeah no idea

slim rock
#

ive been trying to zoom out the whole time

#

just confusing

vestal tapir
#

maybe you can retry it and it will be zoomed out

slim rock
#

no way to reset it either

#

been trying to find a way too

pearl pondBOT
#

@slim rock Has your question been resolved?

pearl pondBOT
#
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Remember:
β€’ Ask your math question in a clear, concise manner.
β€’ Show your work, and if possible, explain where you are stuck.
β€’ After 15 minutes, feel free to ping <@&286206848099549185>.
β€’ Type the command .close to free the channel when you're done.
β€’ Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

quick jewel
#

How do I complete number 7

pearl pondBOT
tall flint
quick jewel
#

I've just been figuring out what kind of equations I could possibly make to get a (first term) or d (difference)

#

I'm not sure what to start with

tall flint
#

"the 11th term is 53" should give you one such equation

quick jewel
#

What would the equation be though

#

I have no examples from the teacher to base it off of

tall flint
#

if you have an arithmetic sequence, what is the 11th term in general?

#

please don't say 53

quick jewel
#

53 = a + 10d?

tall flint
#

that doesn't answer the question i just asked but yes that's one of your equations

quick jewel
#

Sorry lol

tall flint
#

where do you think your second equation comes from?

quick jewel
#

One of the Sn formulas?

#

How would I get the other missing numbers tho

pearl pondBOT
#

@quick jewel Has your question been resolved?

cloud zephyr
cloud zephyr
#

these 2 equations, right?

quick jewel
#

Yeah

#

I have these formulas to work with

pearl pondBOT
#

@quick jewel Has your question been resolved?

pearl pondBOT
#
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β€’ Ask your math question in a clear, concise manner.
β€’ Show your work, and if possible, explain where you are stuck.
β€’ After 15 minutes, feel free to ping <@&286206848099549185>.
β€’ Type the command .close to free the channel when you're done.
β€’ Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

covert nymph
#

Could someone explain why the answer is not DNE or 0? I've tried multiple times?

covert nymph
plush bramble
#

Do you know how to find the slope of a line?

covert nymph
#

yes it's (y2-y1)/(x2-x1)

plush bramble
#

Sure. Do that for the line passing through f(4)

#

Line segment

covert nymph
#

ok so i got

#

the slope is 1/2 and if i plug in (using 5,2) y-2 = 1/2 (x-5) i get y=1/2x - 0.5

plush bramble
#

Yup

#

The slope is 1/2

covert nymph
#

oh ok thank you!

#

i was thinking too hard about it

#

.close

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#
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β€’ Show your work, and if possible, explain where you are stuck.
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β€’ Type the command .close to free the channel when you're done.
β€’ Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

meager fog
#

Back again…. I think I have the math part down. I’m just confused on how I answer.

cosmic garnet
#

where did the middle 100 come from

#

also

#

why are you calculating values with both

meager fog
#

d. f(-100) + (100)

cosmic garnet
#

so you just have to calculate with this

cosmic garnet
midnight haven
#

so basically

#

f(-100) -100 is your x

#

which is ofc <0

#

so you enter case 6x+1

versed ledge
midnight haven
#

then f(100) is ofc >0

meager fog
#

Oooo ok my math teacher literally went over this in the last five minutes of class and was like OK guys go do homework

midnight haven
#

so you enter case >=0

midnight haven
midnight haven
#

its okay we can help

#

that's why we are here for

#

all of us, helpers.

meager fog
#

Ok let’s see if I got it

midnight haven
#

show us

meager fog
midnight haven
#

can you show me your work

#

im lazy to do it on my own πŸ˜›

meager fog
#

lol ya

versed ledge
#

Check again

#

Rest are fine

midnight haven
#

d is not 3 yea

meager fog
#

Would it be 8 (-100)+3=-797?

midnight haven
#

no

#

you dont have the case just f(-100)

#

if it asked you for just f(-100) that would be the answerr

#

but it asks you for

#

f(-100) +f(100)

#

the result from f(-100) you add with the result from f(100)

#

brb

meager fog
#

Oh ok

#

So -797 + 803= 6

#

Brb let me go change that math

midnight haven
meager fog
#

-599+803=204

midnight haven
#

yea

#

good job

meager fog
#

Phew I wouldn’t have thought of that. Thank you guys!! Google and YouTube were not teaching me how to do it!

midnight haven
#

no problem

#

have fun

#

and have a good day

#

i gues

meager fog
#

.close

pearl pondBOT
#
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β€’ Type the command .close to free the channel when you're done.
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Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

hasty crater
pearl pondBOT
#

@hasty crater Has your question been resolved?

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#

@hasty crater Has your question been resolved?

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#

@hasty crater Has your question been resolved?

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stone imp
pearl pondBOT
stone imp
#

I don’t understand how im supposed to know how much x is worth

#

Nvm im stupid

#

.close

pearl pondBOT
#
Channel closed

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stone imp
#

.reopen

pearl pondBOT
#

βœ…

stone imp
#

I’m confused again

wet swallow
#

Is this translatedbleak

stone imp
#

Unfortunately

woeful stump
#

the equation is coffee + roll = juice + cookie

stone imp
#

Won’t it be the same as

stone imp
#

How is it different

woeful stump
#

idk maybe

stone imp
#

They have the same worth and numbers

woeful stump
#

solve and find out

stone imp
#

Okay I try

midnight haven
#

Hello

stone imp
#

It was right

#

I’m not gonna question it

#

I’m just gonna go with it.

woeful stump
#

lol okay

woeful stump
#

confirm they're equal

stone imp
#

Wait 12+7 is 21 Right

woeful stump
wet swallow
#

Lol

stone imp
#

Yeah it juys hit me

#

The way I was so confused when it said it was wrong

#

Okay we’re done with my stupidity here u will probably see me soon again but bye bye for now 😚

#

.close

pearl pondBOT
#
Channel closed

Closed by @stone imp

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stone imp
#

.reopen

pearl pondBOT
#

βœ…

stone imp
#

Hi hi

#

0.01+0.01x=0.1x

#

That’s

#

That’s 0.1111111111 right

#

Right …

#

It says answer algebraically

#

And to answer exactly

#

So I did that

versed bluff
#

May if you Transform it to a fraction Will be easer to solve dontk

stone imp
#

How do I do that

versed bluff
#

Soo You write in the numerator the Hole number whitout comma and below You put a 1 and add ceros as many decimals the number has

stone imp
#

Okay where do I do that

versed bluff
#

<@&286206848099549185>

summer prawn
#

Oh, couldn't you represent all of these by the same denominator?

wet swallow
#

Wut

summer prawn
#

so have like 1/10 = 100/1000

#

also this makes no sense lmfao

wet swallow
summer prawn
#

oh, it uses x

#

😭 bro write it down

wet swallow
#

Convert to fractions

summer prawn
#

$\frac{1}{100}+\frac{1}{100}x=\frac{1}{10}x$

jolly parrotBOT
#

Makenna

summer prawn
#

$\frac{1}{100}+\frac{1}{100}x=\frac{10}{100}x$

jolly parrotBOT
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Makenna

summer prawn
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$\frac{1}{100}=\frac{10}{100}x-\frac{1}{100}x$

jolly parrotBOT
#

Makenna

summer prawn
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can you go from here?

stone imp
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The answer was 1/9 bcs my brother touched the answer button he wasn’t supposed to but I still don’t get it

pearl pondBOT
#

@stone imp Has your question been resolved?

pearl pondBOT
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dusk otter
#

I am trying to prove that associativity is present in this binary operation (i.e. (g+h)^3).
I am not sure how to do the g*(h * i )

torn shell
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you just do the same with h * i first

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g * (h+i)^3=(g+(h+i)^3)^3

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im not sure how its associative though

dusk otter
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it may not be, my job is to checkif it is or not

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but I don't believe it is

torn shell
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so you would need those to be equal

dusk otter
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yeah

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so it's not associative

torn shell
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i think you cna just argue that they are not the same directly from this idk how necessary it is to expand

merry carbon
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(you could try and also find explicit a,b,c such that ((a + b)^3 + c)^3 and (a + (b + c)^3)^3 are diferent)

torn shell
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would comparing terms work too

dusk otter
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Is there a point to the k in the first aprt?

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Idk If I am seeing the purpose there

torn shell
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like you would hasve some g^9 term but not on the other one right

torn shell
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chartbit counterexample works well and is easyh

dusk otter
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hmm okay maybe a counter example would be the better option then

torn shell
#

also for the conclusion the operator * is what is not associative

dusk otter
torn shell
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after g * (h * i):

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you did g * h again

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not h * i

dusk otter
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oh I see I see

torn shell
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well h * i would be (h+i)^3

pearl pondBOT
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@dusk otter Has your question been resolved?

pearl pondBOT
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sand coyote
pearl pondBOT
sand coyote
#

I need to show that the angle is 90 degres

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I know its the dot product

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But how do i apply it

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in this context

merry carbon
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Which angle do you want to show is 90?

sand coyote
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B

merry carbon
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Well, you can effectively rephrase that as saying that the line (segments) AB and BC are perpendicular

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...if that's enough to cook with? KL1Cook

sand coyote
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No i think they want me to proove it with

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Calculations

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I can do Dot product of a and b =0

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But im not sure how to apply that here and which coordinates to use

sand coyote
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To find vector BA, (-2-0; 0-4) and vector BC (8,-4)

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something like this

pearl pondBOT
#

@sand coyote Has your question been resolved?

merry carbon
merry carbon
pearl pondBOT
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deep girder
#

can someone explain this funky rule to me?

pearl pondBOT
frank goblet
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it is called substitution

#

consider the following:

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let u be a function

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u(x)=x^2+1

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note that this is exactly the denominator

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so we get

deep girder
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ok yup

frank goblet
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$5\cdot\int\frac{x}{u}dx$

jolly parrotBOT
#

Martin

frank goblet
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now we dont want u and x

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because remember: u depends on x, so we still have to take it into account when integrating

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since the x-world was not so nice, we wanna completely switch to the u-world

deep girder
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lol

frank goblet
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in order to do so, we have to exchange our dx for a du

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the question is how we do that

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we know that u=x^2+1

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therefore du/dx=2x

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which we can write as: du=2x*dx

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or dx=1/2x * du

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so we get

deep girder
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ahhhhh

frank goblet
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$5\cdot\int\frac{x}{u}dx=5\cdot\int\frac{x}{u}\frac{1}{2x}du=5\cdot\int\frac{1}{2u}du=\frac{5}{2}\cdot\int\frac{1}{u}du$