#help-13

1 messages · Page 318 of 1

crimson sedge
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you take cases

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case 1:

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a > x

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case 2:

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-a > x

dapper mulch
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and the union would be (-a,inf)?

opaque root
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Also, your question is not correct

crimson sedge
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also i dont know which range you have for x

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or anything

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pls just

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!original

cedar kilnBOT
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Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.

dapper mulch
crimson sedge
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hint: sqrt(x) exists if and only if x>=0

dapper mulch
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when i do that

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4-x^2 >= 0
-x^2 >= -4
x^2 <= 4
x <= +-2

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and then the domain goes [-2,2]

opaque root
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You get |x|<=2

dapper mulch
opaque root
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=

dapper mulch
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why doesnt it go +-2 tho?

opaque root
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Because sqrt(x^2) is |x| and sqrt(4) is 2

dapper mulch
opaque root
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U put sqrt in both sides

dapper mulch
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yeah , i wrote it wrong my bad

opaque root
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And u have ti know where things come from

dapper mulch
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doesnt the domain for x>= 2 go [2,inf) and x>-2 go (-2,inf)?

opaque root
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You have this

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|x| <= 2

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Correct?

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We check the limits

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If x = 2

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|2| <=2 is true

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If x>2 that inequality is false

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For example |3|<=2 is false

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Now the other side

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X=-2

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|-2|<=2 is true

dapper mulch
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ok i understand

opaque root
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If x<-2

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Then again is false

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So x is between -2 and 2

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-2 <= x <= 2

dapper mulch
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understanding this way is easier , my teacher was trying to make us find domains of both sperately or smthing

opaque root
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[-2, 2]

dapper mulch
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ty

opaque root
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Welcome

dapper mulch
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.close

cedar kilnBOT
#
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cedar kilnBOT
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tribal bear
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Hello, could someone help me to compute this sum ? Ty !

tribal bear
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(ping me pls)

odd verge
next hornet
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use choose formula

dusk finch
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but yeah, use the factorial form

cedar kilnBOT
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@tribal bear Has your question been resolved?

tribal bear
tribal bear
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but still doesnt work

odd verge
tribal bear
odd verge
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Would it?

cedar kilnBOT
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tribal bear
cedar kilnBOT
odd verge
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Yes

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So n ≥ m too

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So n might = m

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So the sum could be = 1

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Let me solve assuming n≥m

tribal bear
odd verge
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Multiply the two things

tribal bear
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but i'm not able to recognise any special formula

odd verge
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Ok and what did you get

tribal bear
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$\frac{m!(m+c-k)!}{(m-k)!(m+c)!}$

wraith daggerBOT
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5 pl / 3 m

tribal bear
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idk how do u sum that formula

odd verge
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You can't find a definite sum

tribal bear
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prove it

odd verge
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Find the sum of a+b+c
Where + is ordinary addition

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@tribal bear

tribal bear
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no but u still can find a simplified expression

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an expression without the sum

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depending of n and m

cedar kilnBOT
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@tribal bear Has your question been resolved?

odd verge
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a+b+c

cedar kilnBOT
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queen sundial
cedar kilnBOT
queen sundial
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Can someone help me with this?

brave aspen
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I would start by finding the derivative

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Derivative will give you an expression for the slope of the tangent line

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As the first derivative can be thought of as the "tangent line slope generator"

queen sundial
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for derivative i got -1/(x-1)^2

brave aspen
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Did you do quotient rule for that?

queen sundial
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yeah

brave aspen
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If so then yes

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Ok then so that thing is the slope

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Could you write an equation for the tangent line at any arbitrary point?

queen sundial
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can yuo just use point slope?

brave aspen
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Yea any form you like

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Point slope is very convenient

queen sundial
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but then for m should i just plug in -1/(x-1)^2

brave aspen
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Yess

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Exactly

queen sundial
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so would it be y-5=-1/(x-1)^2(x+1)???

brave aspen
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Yea

queen sundial
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but it asks for the equations

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so theres more than one

brave aspen
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Yes

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Because right now

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You have an equation with 2 variables

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You need to find another equation to solve

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Maybe you already have one

queen sundial
brave aspen
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Well the other equation is

queen sundial
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what is the other equation

brave aspen
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f(x) = y

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Because of course the original function should be true

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Then you have the system

queen sundial
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wait can you reiterate the two system equations

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so one is the point slope form

brave aspen
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The other is the original function f

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y = x/(x-1)

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That is also true in this system

queen sundial
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and then i set them equal to each other?

brave aspen
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Yes that's one way

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That will get you the x values where the tangent line equation has the point (-1, 5)

queen sundial
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is there an easier way

cedar kilnBOT
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@queen sundial Has your question been resolved?

crimson sedge
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everyone speak portuguese?????

cedar kilnBOT
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lucid iris
cedar kilnBOT
lucid iris
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im confused

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so i set it up as

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65 = 80e^(-10k)

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and finding k

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i got ln(13/16) / -10 = k

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but when i go to check

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its wrong

dawn junco
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wym check ?

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@lucid iris

tribal bear
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but u can with the sum

lucid iris
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its something with epon growth and decay

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but it was like 80(13/16)^(t/10)

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the asnwer

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i don't understand that part

dawn junco
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well did you try getting the function from the k you got ?

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you know the function is 80*e^kt, that's what you assumed when setting up the equation

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just plug it in

lucid iris
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oh ok

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like plug till it gets 65?

dawn junco
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no

lucid iris
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hm

dawn junco
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you know k=ln(13/16)/whatever

dawn junco
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and simplify

lucid iris
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oh ok

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i see

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.close

cedar kilnBOT
#
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shadow pollen
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hi guys here Does anyone know how I can download and install: LabView"

dire geode
cedar kilnBOT
#

@shadow pollen Has your question been resolved?

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tired crystal
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Can someone please help me I can’t figure out how to isolate theta

tired crystal
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I’m 99% sure I have the derivative right but after that all my work could be incorrect

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And I think you can just disregard the 0.75m since the question has nothing to do with mass my teacher did a question on the bored and he just completely disregarded one of the terms because it didn’t have anything to do with his solution but I could be wrong…

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<@&286206848099549185>

runic garnet
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,w differentiate (0.75sin(x) + cos(x))^(-1)

tired crystal
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Why did you differentiate that equation?

runic garnet
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thats how we maximize?

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thats what u did lol

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it looks like ur off by a factor of -1

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but in the end it doesnt rlly matter

tired crystal
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I differentiated the F=0.75M(0.75Sintheta+costheta)^-1

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Then i set that answer equal to zero

runic garnet
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ya i did the same except without the 0.75M cuz its just a constant

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thats being multiplied

tired crystal
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So I don’t need to include the 0.75M when i differentiate?

runic garnet
tired crystal
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And then I solve for theta right? That’s what I’m stuck on

runic garnet
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$\dv {x} 3x = 3 \dv {x} x$

wraith daggerBOT
runic garnet
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this is basically what im talking abt

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and then once u differentiate and set equal to 0, u just divide both sides by 0.75m

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so it doesnt rlly matter

runic garnet
# wraith dagger

so set the numerator and denominator of this equal to 0, individually

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$\sin(x) - 0.75 \cos(x) = 0 \newline \newline (0.75 \sin (x) + \cos (x))^2 = 0$

wraith daggerBOT
tired crystal
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I just can’t understand it, pissing me off would you just restart completely if you were me and use that derivative you showed me?

runic garnet
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the derivative i showed u is exactly what u had, except u were off by a factor of (-1)

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look at the last line where u wrote F'

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thats what i got

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that last simplified thing

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@tired crystal see it?

tired crystal
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Not really lol

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Anyway you can voice call quick?

runic garnet
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nah

tired crystal
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Like that f’ is completely different

runic garnet
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no its not

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look what u simplified to

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bro just look 😭

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u have it right there

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right underneath

tired crystal
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That’s not simplified the line down I set it equal to zero and moved the 0.75/0.75sintheta +cos theta over on the other side

runic garnet
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honestly i think u just have to add the fractions

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but looks like ur missing an 'm' somewhere

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so maybe u shd restart

tired crystal
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You can just disregard the m

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All I need help with is isolating theta

runic garnet
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dont u have to show work? if u just ignore it, it wont make sense

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id say just restart

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its not that intensive of a derivative anyways

tired crystal
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So how would you approach it?

runic garnet
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$fm \dv {F}{\theta} [(f \sin(\theta) + \cos (\theta))^{-1}]$

wraith daggerBOT
tired crystal
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Okay so I’ll do that quickly give me a sec

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Correct? And then set that equal to zero?

runic garnet
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not correct

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u brought the -1 to the inside

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instead of the outside

tired crystal
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So just make that whole bracket on the bottom negative?

runic garnet
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no

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because the negative doesnt distribute to the square like that

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u have to keep the negative on the outside

tired crystal
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Im sorry im actually an idiot

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So at the top then?

runic garnet
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yea that works, u can do that if u want

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and keep the fm outside the dF/dtheta

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and then just divide it out when u set equal to 0

tired crystal
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So now I set that equation equal to zero?

runic garnet
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well show me the equation

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oh wait

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u sent it lol

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lemme see

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yea, on the top, it should be (-1)(0.75cos - sin)

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parentheses around everything

tired crystal
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Okay done

runic garnet
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otherwise, it looks like the - is only for the cos

tired crystal
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Can I distribute it into the brackets

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Making it + sin and -cos

runic garnet
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correct

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did u keep the fm there too

tired crystal
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So that’s where I’m at once I set equal to zero and move the denominator over

runic garnet
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wait wait

tired crystal
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I didn’t keep fm

runic garnet
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ok u should divide both sides by fm to get rid of it with the 0

runic garnet
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but anyways

runic garnet
tired crystal
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To isolate theta I thought

runic garnet
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but whats on the other side of the equals sign

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in the previous line

tired crystal
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Just df/dtheta

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I thought no?

runic garnet
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right

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now, rewrite ur derivative and set equal to 0

tired crystal
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And then you just set your derivative to zero

runic garnet
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then we will go from there

tired crystal
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Okay

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I’m confused about dividing the fm part out

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Since we don’t need it since it’s a constant I don’t even think he will care if I include it or not

runic garnet
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well if its in the original formula, i suggest keeping it in, just to be safe

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but if u feel its fine, then we'll move on

tired crystal
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He had an example where he just got rid of it when he set equal to zero

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So wait how do I do it? I will just to be safe

runic garnet
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right, thats what im suggesting to do

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u have to keep it for all the steps until u set equal to 0

tired crystal
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If would be 0.75m correct?

runic garnet
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yea, sure, or u could keep it fm

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doesnt rlly matter

tired crystal
runic garnet
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ok well close lol

u forgot the 0.75m on the top right

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and it should be on the other side of the second dF/dtheta

tired crystal
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Lmao I’m really sorry

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Where do I put it on the top right sorry

runic garnet
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ok see on line 1

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u differentiated and u got

tired crystal
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Yes

runic garnet
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(-1)(0.75sin - cos)^-2 ...

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right there

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the 0.75m just disappeared

tired crystal
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Yes so can I just put it infront of that whole equation?

runic garnet
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yea

tired crystal
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Okay

runic garnet
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and then on the second line

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it should be on the other side of the equation

tired crystal
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It’s Going to be messy I’m going to fix it after I solve

runic garnet
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lol line 2 still

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other side of the equation, not other side of the dF/dtheta

tired crystal
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Ohhh okok

runic garnet
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ok now when u set it equal to 0

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u didnt distribute the -1

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u only gave it to the -0.75cos

tired crystal
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Oh my bad should be +sin

runic garnet
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yea

tired crystal
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I was working on this shit for like 2 hours and it just hurt my brain plus im working rn I feel brain fried

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Ok it’s corrected

runic garnet
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ok cool

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so now, to find critical points,

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set the numerator equal to 0

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and set the denominator equal to 0

tired crystal
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Separately?

runic garnet
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yes

tired crystal
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Done

runic garnet
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ok, now we want to solve

tired crystal
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Can I move sin over and then cos over making it 0.75=sintheta/costheta which will equal tantheta and then move tan to the other side by taking the inverse?

runic garnet
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$\sin (\theta) = 0.75 \cos (\theta) \newline \newline (0.75 \sin (\theta) + \cos (\theta))^2 = 0$

wraith daggerBOT
tired crystal
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For the first line right what about the other one we set equal to zero that’s squared what happens to it

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Would be -0.75 actually

runic garnet
tired crystal
runic garnet
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still not understanding how its -0.75

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tell me ur steps how u got that

tired crystal
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Oh actually nvm I’m overthinking it

runic garnet
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well what did you do

tired crystal
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I have no idea now that I look at it again what I was thinking

runic garnet
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yea, i mean add 0.75cos() to both sides, and then u get tan() = 0.75

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so what do u have for the first eqn

tired crystal
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So taninverse(0.75) right?

runic garnet
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yea arctan(0.75)

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thats a potential angle

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but we have to check the others first

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so now onto the second equation

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what do u think we should do

tired crystal
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I would say expand the brackets and then foil but idk

runic garnet
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no

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if we had the eqn

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(4x)^2 = 0

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how would u solve

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without expanding/distributing the exponent

tired crystal
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Make it a root? Idek tbh I’m lost abit

runic garnet
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wdym by make it a root

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not tryna be rude or anything, but this stuff should be second nature to you if ur doing calculus

tired crystal
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No offence taken lol, we are just starting up classes again and I’m in a college course for instrumentation control engineering technology last year was just basic derivatives and integrals that I found very easy and some of this stuff is just weird to me

runic garnet
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ah ok i see

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alr

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so for the second eqn, wdym by make it a root

tired crystal
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Like turn the power into a square root but I guess you kinda can’t even do that like it wouldn’t make sense

runic garnet
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u cant "turn" the power into a sqrt

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but u can take the sqrt of both sides

runic garnet
tired crystal
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doesn’t it just become 4x

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We did that last year I forget lmao

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Because square root of 0 is just 0 and the square root will cancel the power out

runic garnet
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yea, so what does the equation become

tired crystal
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4x=0

runic garnet
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good

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now back to ur problem

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what should we do

tired crystal
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Take the square root of both sides

runic garnet
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yes

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what do u get upon doing that

tired crystal
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0.75sintheta+costheta

runic garnet
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give me the full equation

tired crystal
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Excuse how messy it is

runic garnet
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ok now what should u do

tired crystal
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Same as last time?

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Wait no we can’t

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Can’t do that either fuck

runic garnet
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how did u get 0.75 + cos

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it was 0.75sin

tired crystal
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Can I do that?

runic garnet
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no

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if u divide one term by 0.75, u have to divide all terms by 0.75

tired crystal
#

Would that be the right approach to do?

runic garnet
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no

tired crystal
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Hmmmm

runic garnet
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u wanna get the sin and cos on opposite sides

tired crystal
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Okay

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So

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0.75sintheta=costheta

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-costheta

runic garnet
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yes

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now what

tired crystal
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Now divide sin over?

runic garnet
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keep going

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on the right track

tired crystal
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I forget what -cos/sin equals isn’t it cot?

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So it would it be -cottheta

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We haven’t learnt to much about those trig functions yet

runic garnet
#

yes

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so -cot(theta) = 0.75

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so now what

tired crystal
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We would isolate theta from -cot

runic garnet
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ok but how

tired crystal
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We haven’t learnt much about those trig functions at all

runic garnet
#

well its basically exactly what u did with the tan

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remember?

tired crystal
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What’s the inverse of cot

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Yes

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Is there a cot inverse button on calculator?

runic garnet
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not sure

tired crystal
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But is that what you would do?

runic garnet
#

but yea its arccot

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so -cot = 0.75

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cot (theta)= -0.75

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then take arccot of both sides

tired crystal
runic garnet
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yes

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,w arccot(-0.75) in degrees

runic garnet
#

what does that solution tell u

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in a physical context

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like reading the problem

tired crystal
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That the angel that minimizes the force would be 36.87degrees

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Our first solution

runic garnet
#

and why is that?

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why not the -53.13?

tired crystal
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Because that would also be 126.87 degrees which is larger

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Than the 36.87

runic garnet
#

not quite

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if we're pulling something at a negative angle, what does that mean

tired crystal
#

Abit confused

runic garnet
#

that means ur pulling from the floor

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like an angle of depression

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but the problem states that we're pulling at an angle of elevation

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meaning it cant be a negative angle

tired crystal
#

Okok I understand now

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Brother thank you so much

runic garnet
#

yea np

tired crystal
#

So that’s our final answer it’s all good?

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Wanna check this over quick you’re a genius lmao

runic garnet
#

should be right

runic garnet
tired crystal
#

Yes you are

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What did you major in or what did you take

runic garnet
#

its free and really good

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just type these in ther

tired crystal
#

Okok

runic garnet
tired crystal
#

Appreciate it man and that’s awesome

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I might branch out into electrical engineering if I can wrap my head around some of this stuff I’m in Canada idk about your our education system is wonky

runic garnet
#

i see

tired crystal
#

You*

runic garnet
#

yea im from the nyc area

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alr gl

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cya

tired crystal
#

Yessir, again thank you so much brother you’ve been great help

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Have a good night man

runic garnet
#

u2

cedar kilnBOT
#

@tired crystal Has your question been resolved?

cedar kilnBOT
#
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limpid brook
cedar kilnBOT
limpid brook
#

Gr 12 data management!

#

so for e) i did it correct and i did 126 - (5C1 x 4C4)

#

but i dont understand why im getting the wrong answer for f???

#

I wrote:

126 - (4C2 x 5C3) - (4C1 x 5C4) - (4C0 x 5C5)

#

and instead of getting 45 (which is the answer), im getting 46??

#

nvm

#

i got it

#

zlol

#

ik why

#

.close

cedar kilnBOT
#
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tired crystal
#

Just looking to have these answers looked over if I messed up where did I go wrong?

cedar kilnBOT
#

@tired crystal Has your question been resolved?

tired crystal
#

No

#

<@&286206848099549185>

tired crystal
#

Do you think I can show my steps anymore to get anymore marks or should that get me full marks?

#

Teacher is a weird marker he will take them out for not putting brackets in right spot n stuff

dreamy void
#

in an exam i wouldn't waste too much time on making it obviously clear

tired crystal
#

It’s not a exam just a assignment, thank you

#

Just wanna make sure I get perfect on it lol

cedar kilnBOT
#

@tired crystal Has your question been resolved?

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full matrix
cedar kilnBOT
full matrix
#

i wanan do $-b/2a$

wraith daggerBOT
full matrix
#

but i don't have a B what do i do

#

do i just set it 0?

livid hound
#

4x^2 - 6 = 4x^2 + 0x - 6
b = 0

full matrix
#

so my equation would be $4x^2+0x-6$

wraith daggerBOT
full matrix
#

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oblique moth
#

How can I do this? And what is the answer?

odd seal
#

is that a 1/a or 1/9?

#

whatever it is, substitute it where "t" is, then evaluate it

oblique moth
cedar kilnBOT
oblique moth
#

Hmm well I'm sorry, but I'm asking this because I tried to do it by myself and I don't know if it's correct.

worldly chasm
#

That looks correct to me, but you can simplify the expression

odd seal
#

make it look nicer

worldly chasm
#

Multiply by a^2/a^2

#

But be sure to also note that a≠0

oblique moth
#

I still don't understand how. 😅

worldly chasm
#

\begin{align*}
f(t) &= \frac{2t}{t^2 + 1} \
f\qty(\frac1{a}) &= \frac{2 \frac1{a}}{{\qty(\frac1{a})}^2 + 1} \
&= \frac{\frac{2}{a}}{\frac1{a^2} + 1} \
&= \frac{\frac{2}{a}}{\frac1{a^2} + 1} \cdot 1 \
&= \frac{\frac{2}{a}}{\frac1{a^2} + 1} \cdot \frac{a^2}{a^2} \
&= \frac{\frac{2}{a} \cdot a^2}{\qty(\frac1{a^2} + 1) \cdot a^2} \
&= \frac{2a}{1 + a^2}
\end{align*}

#

(subject to the restriction that a ≠ 0)

#

@oblique moth ^ does the above help?

oblique moth
#

.close

cedar kilnBOT
#
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worldly chasm
#

No stop come back

#

The point wasn't to work the answer just, do you understand the steps?

#

.reopen

cedar kilnBOT
#

worldly chasm
#

Like can you explain why I multiplied by a^2/a^2

#

Hi you're back with me again 👋

oblique moth
oblique moth
worldly chasm
#

Yes, but why a^2 / a^2 specifically and not some other value

#

What about your expression above shouts to me that a^2/a^2 specifically should be the form of 1 that I multiply by?

oblique moth
worldly chasm
#

Because in the denominator you have 1/a^2 and that's the largest power of a in any denominator in the fraction

#

So if I multiply everything in the fraction, top and bottom, by a^2, then I'll be left with a regular fraction rather than a compound fraction

worldly chasm
#

So if I showed you the following fraction, what would you multiply by?

[
\frac{\frac1{ab} + \frac{b}{a^2}}{\frac{a}{b^3} - \frac{1}{ab^2}}
]

wraith daggerBOT
#

OmnipotentEntity

worldly chasm
#

Would b^3 / b^3 cancel out any of the a's in the denominator?

oblique moth
#

🥹

worldly chasm
#

It's a little tricky, but the answer is a^2 b^3 / a^2 b^3

#

Because you need a^2 to wipe out all of the a's (the largest power of a is found in b/a^2), and you need b^3 to wipe out the b's.

worldly chasm
#

Yup! Exactly correct

oblique moth
worldly chasm
#

Yup

oblique moth
worldly chasm
#

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#
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worldly chasm
#

Thanks for sticking around!

cedar kilnBOT
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versed fulcrum
#

Hello

cedar kilnBOT
versed fulcrum
#

Not sure why this is wrong

worldly chasm
#

!show

cedar kilnBOT
#

Show your work, and if possible, explain where you are stuck.

versed fulcrum
#

30 = v(3.9) -> v = 30/3.9

#

60 = v_avg(10.8) -> v_avg = 60/10.8

versed fulcrum
worldly chasm
#

So if we let v_boat be the speed of the boat, and v_river be the speed of the river, then we have

3.90 hr (v_boat + v_river)km/hr = 30.0 km
6.90 hr (v_boat - v_river)km/hr = 30.0 km

#

Do you see why? @versed fulcrum

versed fulcrum
#

I understand that

#

I guess substitution is the best way?

worldly chasm
#

That's one way

#

You can also just eliminate v_boat by subtracting the two equations from each other

#

Well you need to divide both equations by 3.9 and 6.9 first

#

Respectively

versed fulcrum
#

Okay

#

I see

#

Thank you so much!

#

.close

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torn lake
#

.close

#

.close

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serene bison
#

determine the intervals on which the function is continuous: f(x) = [[x+3]] looks like this (look at image), can someone explain what this means?

muted bear
#

your book or teacher should have specified

#

thats not standard afaik

serene bison
#

hmm, do you know what it is stood for commonly for

#

or it can basically be anything

idle crystal
#

normally [] is used for the floor functions sometimes but ive never seen [[]]

muted bear
#

i have also seen it used for floor

#

but there are many ways people write floor

hot crag
#

interestingly, those double brackets are used in things like R[[x]] to mean the ring of all formal power series in x with real coeffs

serene bison
#

the answer says its discontinuous at c and continuous at (c,c+1) for all integers

hot crag
#

probably floor then

serene bison
#

what is floor exactly

hot crag
#

rounding down

#

floor(3) = 3

#

floor(3.4) = 3

#

floor(-1.5) = -2

#

etc

serene bison
#

so like this

hot crag
#

uhhh

#

not quite

#

oh wait no nvm

#

that's correct, yeah.

#

the color scheme confused me

serene bison
hot crag
#

no the example is correct

serene bison
hot crag
#

just

#

look at the graph?

#

do some limits?

serene bison
#

so [x+3] means it starts from 3 and rounds down?

#

im confused

#

<@&286206848099549185> hi can i get brief explanation

native heath
#

Heya!

serene bison
#

how does the floor of x+3 work

native heath
#

I assume that's just floor?

serene bison
#

yes

native heath
#

Can you try floor(x)

serene bison
#

or ren deducted it to be

serene bison
serene bison
#

c i assume is x?

#

are you asking a question to clarify

#

or like to make me think

#

i think i get it

#

thanks

#

.close

cedar kilnBOT
#
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native heath
#

..lmao

serene bison
#

?

cedar kilnBOT
#
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gilded plume
#

when should we rationalise the denominator in trigonometric identities

cedar kilnBOT
#

Please don't occupy multiple help channels.

gilded plume
#

@old ridge

tropic jay
gilded plume
#

the second step

#

but we can solve it by seperating 1/secA and 1/Tan A

#

@old ridge

#

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tropic jay
#

So it's upon you which way you can make it work

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hybrid leaf
#

please help me in grade 9 math i dont quite understand how to solve quadratic equations by completing the square

high bridge
#

yall do quadratics in grade 9?

hybrid leaf
#

yeah im so cooked

high bridge
#

don't be, it is more simple than you think

idle crystal
void spoke
#

Let's say you have a quadratic ax^2+b-x+c=0

high bridge
#

in canada it is grade 11

idle crystal
#

HUH

void spoke
#

Steps to solve a quadratic by completing the square method.

hybrid leaf
#

dang

bleak viper
high bridge
#

although i learned it in grade 7 in china...

hybrid leaf
idle crystal
#

were getting off topic lol

void spoke
#
  1. Make the coefficient of x^2 as 1
hybrid leaf
#

hahahah

void spoke
high bridge
#

yeah let oppailol cook

void spoke
#

Ok so 1st step

hybrid leaf
#

ok tysm

void spoke
#
  1. Make the coefficient of x^2 as 1
#

So now if the quadratic is ax^2+bx+c=0

hybrid leaf
#

i should write this down

void spoke
#

How can you make the coefficient of x^2 as 1? Think

hybrid leaf
#

x = 1?

#

😭

void spoke
#

Do you know what is the meaning of coefficient?

#

Relax don't cry

#

9th graders don't cry

hybrid leaf
#

no sir

void spoke
#

Do you what is the meaning of coefficient?

hybrid leaf
#

i dont

void spoke
#

Ok let me explain

hybrid leaf
#

wait

#

is it the ²?

void spoke
#

No no

hybrid leaf
#

🤧

void spoke
#

the power is the degree of that term

#

leave let's make it simple

hybrid leaf
#

okay

void spoke
#

We have quadratic
ax^2+bx+c=0

#

Now coefficient is simply the number/term multiplied to a power of x

#

Like for example

#

x^2 is multiplied with a

#

So it's coefficient is a

#

x is multiplied with b

#

So it's coefficient is b

hybrid leaf
#

i see

void spoke
#

Take your time and tell do you understand it

hybrid leaf
#

the letters next to x?

#

is it

void spoke
#

In general form

#

Its letters but it is actually numbers

high bridge
hybrid leaf
#

because it represents 1?

void spoke
#

He gave you the definition you could write

#

Ok now did you understand it?

hybrid leaf
#

i do

void spoke
#

Good

#

Ok now tell me

#

the quadratic is 2x^2+4x+6

#

What is the coefficient of x^2

hybrid leaf
#

its 2?

void spoke
#

Sure?

hybrid leaf
#

yes

void spoke
#

Good

high bridge
#

ok a more complex one: tell me the coefficient of this term: 18645xyz^152

void spoke
#

I wanted to see the confidence

hybrid leaf
#

yes!

void spoke
#

note: coefficient is a CONSTANT number that is MULTIPLIED with a VARIABLE

#

Remember this is the general definition

high bridge
#

nice

void spoke
#

Good

#

Ok so we move to step 1 now

#

1.Make the coefficient of x^2 as 1

hybrid leaf
#

okay

void spoke
#

Now let's say we have
ax^2+bx+c=0
How will you make the coefficient of x^2 as 1

#

Think take your time

hybrid leaf
#

divide?

void spoke
#

Ok

#

But divide by what?

high bridge
#

divide by ?

hybrid leaf
#

divide by a

void spoke
#

Yes he is understanding

#

Good

#

Ok so you divide by a

#

Now after dividing by a what will you get?

hybrid leaf
#

x² is 1

void spoke
#

x^2 or coefficient?

#

Be confident and answer

hybrid leaf
#

coefficient

void spoke
#

Good

#

Ok we had ax^2+bx+c=0
You divided by a
So what will you have now

#

Think

hybrid leaf
#

wait

void spoke
#

Ok

hybrid leaf
#

umm

#

can i send a image from my book

void spoke
#

Ok

hybrid leaf
void spoke
#

Oh

high bridge
#

your textbook is over-complicating it.....

void spoke
#

So they don't want to do the standard way

hybrid leaf
void spoke
#

They want to do the fashion way

#

Ok so what we do is

hybrid leaf
#

fashion way sucks

void spoke
#

Ik

#

But quick question

hybrid leaf
#

?

void spoke
#

1.Is it necessary for you to do according to the book

#

Or you can become Gauss?

hybrid leaf
#

i think it is necessary

void spoke
#

Oof

high bridge
#

oof

void spoke
#

Oh no

hybrid leaf
#

💀

void spoke
#

Ok so let's take a different way to the answer

#

you know (a+b)^2 ?

hybrid leaf
#

oh okay

#

i dont

high bridge
#

step 1: recognizing binomial squaring pattern

void spoke
#

No

#

💀☠️

#

Bro speaks facts but tough

high bridge
#

ok let's start from 0 then

void spoke
#

Yes

#

Do you know (a+b)^2

#

C?

hybrid leaf
#

i dont

high bridge
#

um you know your distributive properties right?

hybrid leaf
#

no 😭

#

im dumb

high bridge
#

like 2X(3+5)=2X3+2X5

void spoke
#

Okok

#

See

#

I belive he knows

#

He learning quadratic he might be knowing it

hybrid leaf
#

oof

void spoke
#

Say yes C 💀

high bridge
#

they probably just didn't recognize the name

high bridge
void spoke
#

Do you know ax(b+c)=axb+axc ?

hybrid leaf
void spoke
#

💀☠️

high bridge
#

huh????

hybrid leaf
void spoke
#

Bro how are you studying quadratic then

hybrid leaf
#

frick

void spoke
#

What

hybrid leaf
void spoke
#

Bro was right

#

He is cooked

high bridge
#

bruhhhh you are studying ahead???

void spoke
#

But still 9th graders don't cry

#

They face it fr

hybrid leaf
#

thats the same with what i was taught

high bridge
#

oh ok

void spoke
#

Ok so we begin with properties of multiplication

#

💀☠️

hybrid leaf
#

can i send it

high bridge
#

let's actually start at 0 ig lol

void spoke
#

What ?

void spoke
#

Lol

#

You will send what you are taught?

hybrid leaf
#

i can understand the first things

void spoke
#

You understood coefficient that's great

#

But there are two problems

#

1.you need to do the book way
2.you don't know the d I s tri butive property

hybrid leaf
#

like example for x² + 4x -12 = 0

high bridge
#

nonononono

#

you are currently not ready for this

high bridge
#

you need to know your basics before you start quadratics again

hybrid leaf
#

i forgot 💀

#

but i ask for one last help so i can understand

high bridge
#

basically, the distributive property is a law of multiplication that ALWAYS works

#

for example:

#

if you do 2X(3+5)

void spoke
#

Ok

high bridge
#

it gives you 16

#

and if you do 2X3+2X5

#

it still gives you 16

#

notice how you can brea apart the bracket into 2 sections?

#

that is how distributive property works

hybrid leaf
#

yesss

high bridge
#

so you recall distributive property now?

hybrid leaf
#

i do

high bridge
#

good, now let's go to this

#

(a+b)^2

#

when you square something, it is basically multiplying it by itself

#

so (a+b)^2 can be turned into this (a+b)X(a+b)

hybrid leaf
#

mhm

high bridge
#

now if you use distributive property on the first a+b you get this

#

(a+b)Xa+(a+b)Xb

#

now use distributive property again you will get this

#

aXa+aXb+aXb+bXb

#

remove the multiply sign cause algebra do not like it

#

a^2+ab+ab+b^2

#

combine the two ab terms

#

a^2+2ab+b^2

#

so there we go, you get this

#

(a+b)^2=a^2+2ab+b^2

#

that is your binomial square expansion (formula?, different places decides to call it formula or not)

hybrid leaf
#

(a+b)² = a² + 2ab + b²

high bridge
hybrid leaf
#

okay

#

i get it

high bridge
#

nice now next step

#

notice how your equation is ax^2+bx=c?

hybrid leaf
#

yeah

high bridge
#

so your way of doing it is multiplying both sides by 4a

#

you should try

hybrid leaf
#

4a(ax² + bx) = 4ac

high bridge
#

yes now use distributive property, break the bracket

hybrid leaf
#

4a^2x^2 + 4abx = 4ac

high bridge
#

nice

#

notice how 4=2^2?

hybrid leaf
#

wait

#

why =

high bridge
#

lmao 2 squared is 4

hybrid leaf
#

my brain is overheating

high bridge
#

ummmmm, maybe you should come back next time?

#

take a rest if you cannot handle it

hybrid leaf
#

i should!

#

mad mod bro thank you so much for the help

high bridge
#

np

hybrid leaf
#

ill try to understand better

high bridge
#

and when would you like to meet next time?

hybrid leaf
#

@void spoke too

hybrid leaf
high bridge
#

ok

#

ig cya

hybrid leaf
#

i feel like its about to turn into free online tutoring 💀

hybrid leaf
#

.close

cedar kilnBOT
#
Channel closed

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hybrid leaf
#

.close

cedar kilnBOT
#
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balmy breach
cedar kilnBOT
balmy breach
#

Here can I just consider volume to be a function of diameter?

normal cipher
#

Yes

#

Volume is 3/4 r^3 π or something

balmy breach
#

that would mean, $$V=(3(2x+1))^3\times \frac{4}{3}\pi$$

normal cipher
#

Then dy/dx

balmy breach
#

and then differentiate this wrt x?

wraith daggerBOT
#

PianoDolphin

cedar kilnBOT
#

@balmy breach Has your question been resolved?

#
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ivory gull
cedar kilnBOT
ivory gull
#

why do they divide by 2?

#

i don't get their reasoning. i understand how they got 25! tho

raven shard
#

25! instead of 26! accounts for the fact the necklace can be rotated
division by 2 accounts for the fact the necklace can be mirrored/flipped

ivory gull
#

what does being " worn either way around" mean?

cedar kilnBOT
#

@ivory gull Has your question been resolved?

ivory gull
# ivory gull

this is a necklace and i don't get how the necklace can be mirrored

#

when a necklace looks like that

cedar kilnBOT
#

@ivory gull Has your question been resolved?

cedar kilnBOT
#
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#
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brave nova
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I have ask this question once but I forgot to check the notifications, i am sorry. Can you guys please help me with this question again. I don't know how to differentiate it using chain rule. I have found x, x= 4 or 1.

fiery plaza
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!occupied

cedar kilnBOT
#

Someone else is already using this help channel. If you need help with a question, please open your own help channel/thread (see #❓how-to-get-help for instructions).

fiery plaza
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Misstyped it, edited^

brave nova
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oh I was confused

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thank you

fiery plaza
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That's just the rearranged formula btw

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Does that give you an idea of how to differentiate it?

brave nova
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is it -1/(x-5)^2 ?

fiery plaza
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You forgot about something

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And your power is wrong

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y = x + 4(x-5)^-1

Type out the steps you do 1 step at a time

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Just focus on the 4(x-5)^-1

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Then I can correct you, at the end I'll summarise the method if you haven't quite got it

brave nova
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thanks I will try again just a min

fiery plaza
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np

brave nova
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dy/dx = 1 - 4/(x-5)^2 ?

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Idk how to proceed step by step cuz the questions before weren't like this.

fiery plaza
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Okay, it was a bit confusing because you didn't keep it in the same format as me which is why I asked for step by step and not the answer, but yes

so, we rearranged the original to get 4(x-5)^-1

You multiply the whole thing by the power

-4(x-5)^-1

You lower the power by 1

-4(x-5)^-2

Then you multiply by the differential of what's inside the brackets
Differential of x-5 is just 1

So your answer is -4(x-5)^-2

If you want it in fraction form then you are completely correct, that gives you -4/(x-5)^2 !

brave nova
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Thank you. in no.5 i can just assign "u = x-2" and y= 8/u^2 then dy/du = =-16u^-3. But i didn't know how to do step by step with this one.

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So it's correct now? Thank you so much for helping me. happy

fiery plaza
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But yeah everything up to that point looks correct

brave nova
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Hey i got the answer correct. Thank you so much

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.close

cedar kilnBOT
#
Channel closed

Closed by @brave nova

Use .reopen if this was a mistake.

cedar kilnBOT
#
Available help channel!

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Remember:
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After 15 minutes, feel free to ping <@&286206848099549185>.
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midnight linden
cedar kilnBOT
midnight linden
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what is this

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oh

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wait nm

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nvm im good

cedar kilnBOT
#

@midnight linden Has your question been resolved?

cedar kilnBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

cedar kilnBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
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lusty pawn
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use vietas formulas

crimson sedge
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Is this a test?

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You aren't supposed to ask test questions in this server

fallen silo
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Put x = 1/2-alpha and find the value of alpha

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Then substitute that value of alpha in the question

crimson sedge
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It's unmarked 🤨

brazen dagger
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Be careful next time @weary pike , you can ask doubt but no live test questions

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<@&268886789983436800> FYI^^

fallow steppe
#

.close

cedar kilnBOT
#
Channel closed

Closed by @fallow steppe

Use .reopen if this was a mistake.

#
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devout wing
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i need help with 3b please. it's non-exact differential equation

honest rover
#

50 runes for 25 dollars
150 runes for 50 dollars
500 runes for 150 dollars
evaluate how good of a deal 150 runes and 500 runes are from 50 runes

lusty pawn
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!occupied

cedar kilnBOT
#

Someone else is already using this help channel. If you need help with a question, please open your own help channel/thread (see #❓how-to-get-help for instructions).

devout wing
#

<@&286206848099549185>

cedar kilnBOT
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@devout wing Has your question been resolved?

devout wing
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yes please

covert cipher
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you just need to make 2 key observations

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try distributing the dx and dy and arrange the like terms together