#help-28

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hazy onyx
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thank you

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torn jolt
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how do i solve this ?

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kindred grove
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have you tried a) or something ?

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if you know what cofactor expansion is, it's not like there 3million ways to do that

hazy onyx
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Factorials:
8 sits,
4 boys,
4 girls,
must seat therefor 2 kids of the same sex can't seat next to each other
how many possible combinations

kindred grove
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this channel is already taken

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you can go in #help-46 for example, it is free at the moment

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@hazy onyx

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@torn jolt still here?

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gilded tapir
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arethmatic sequences third member is positive and it is 5/3 part of the fifth member. how many members of the sequence are positive

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gilded tapir
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<@&286206848099549185>

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void nova
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You have $a_1 + 2d > 0$ and also $a_1 + 2d = \frac{5}{3} (a_1 + 4d)$

glossy valveBOT
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Alberto Z.

void nova
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This because the $n^{th}$ general term of an arithmetic sequence is $a_n = a_1 + (n - 1)d$

glossy valveBOT
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Alberto Z.

void nova
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From the 2nd equation you get $a_1 = -7d$

glossy valveBOT
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Alberto Z.

void nova
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Which gives the first to be $d < 0$

glossy valveBOT
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Alberto Z.

void nova
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Hence, $$(n - 8)d > 0 \Rightarrow n-8 < 0 \Rightarrow n < 8$$

glossy valveBOT
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Alberto Z.

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Alberto Z.

void nova
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Thus, only the first 7 numbers are positive
(because n < 8 is equivalent to n ≤ 7, since we're working with whole numbers)

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slender pond
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what does differentiating give me the max value of r?

short niche
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when the derivative is zero, we get a local minimum, local maximum or inflexion point

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all local maximas must lie on some point where the derivative is zero

slender pond
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so did the person in the video assume that its the local maximum?

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since it could have been the minimum or inflextion point

short niche
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i guess

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but from the diagram u can tell its on the circle

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the only one not on the circumference is 0

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to show it is a bit of work

slender pond
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oh ok

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ty

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wicked cliff
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why is 0 , pi and 2pi?

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lone venture
wicked cliff
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if are cosine then is 3pi/2 and pi/2

wicked cliff
lone venture
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if cos(theta) = 0, then yes

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mighty grove
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mighty grove
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I need help with iv)

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this is the solution

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why is it 7/12 and not 5/12?

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when it intersects the 1500 line at 5/2 and 15/2

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does that not mean the first lot is 2.5 months, second lot is 5 months, ans third lot is 4.5 month ?

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so its 5/12 ?

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but i find if you account for first 10 months then you get 7/12

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i need help 😭😭😭

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split swift
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it's because it's starting from march

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I'm assuming the graph is plotted with 0 being jan 1st

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but if you shift it along by 3, you begin with the population being <=1500

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so you get 5/10 for the first 10 months

mighty grove
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are we able to make that assumption?

split swift
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then the next period begins with <=1500 again

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where's the graph from

mighty grove
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it was given to me by someone who was showing me their solution

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since i got 5/12, and the answer was apparently 7/12

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and this is the solution they gave me for it

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but i just couldn’t understand it still

split swift
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if the graph begins with 0 being march 1st then 5/12 looks more reasonable

mighty grove
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do you reckon it’s a mistake and the answer is 5/12? or you have to make the assumption it wants from when march starts and onward?

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it would make more sense in that idea to mention a restriction in domain though

split swift
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rereading the question, it looks like it does want the graph to start with 0=march, so it's probably a mistake

mighty grove
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okay thanks

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torn jolt
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If I evaluate a limit and get 0^- from the left side and 0^+ from the right side, is the answer just 0 for both and so the limit exists or are the answers different and so therefore the limit does not exist?

alpine vigil
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limits of both sides converge to 0 so safe to say it exists

umbral dome
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that just says which direction they approach 0 from, approaching 0 from above or below is still approaching 0 so it does exist

alpine vigil
torn jolt
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Alright, got it, thanks a lot

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torn jolt
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is this implying leibnez notation?

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nimble dust
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i dont think so

torn jolt
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ok just checking

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thanks

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signal bolt
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I am stuck. I was thinking of using the geometric dot product to help solve it but i don’t know if it did anything

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opal isle
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you could sketch the problem

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not sure if you can do it this way

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wispy marsh
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Why is r=3 but the circle has a radius of 1.5

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Please don't occupy multiple help channels.

wispy marsh
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Mb didnt mean to have 2 channels

spiral vigil
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real musk
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for part c, how did they find the values of j for both Fs?

real musk
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remote terrace
# real musk

its just trig, remember soh cah toa. For the 95N force, the j component (opposite) it is o/h = sin(73), or o = h*sin(73), where h is the hypotenuse, (aka the magnitude) of the force, in this case 95N

real musk
remote terrace
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-95cos(73) = -27.78,
95sin(73) = 90.85, etc.

remote terrace
remote terrace
# real musk thank you

no prob, just be careful to account for the direction of the i and j components. In this case, make sure you note that the i component is in the -i direction, so make sure you calculate it as -95cos(73)

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hard gate
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Hey

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hard gate
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The thing that always confuses me on sequences is what the n means

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what is the n+1 mean after (-1)

supple sail
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n is basically the number of term

hard gate
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dont understand

supple sail
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like you are given the first term

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you need to find next 4

hard gate
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so n+1 is 2

supple sail
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n can be any natural number

hard gate
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So how would I do T2

supple sail
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put n = 1

so we have this relation
T2 = -(1)^(1+1) 2T1

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which is 1 times 2 times 3

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= 6

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so ur second term is 6

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you just keep on putting n= 1 then 2 , 3 , 4

hard gate
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So t3= -1^(2+1) 2T2

supple sail
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you got it

hard gate
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-1x6

supple sail
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= 1

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this is called alternating series

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so you get first term positive
next you get negative nd so

hard gate
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I got -1 from squaring -1

supple sail
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you're prolly doing it wrong

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dont do this
-1^2

do this

(-1)^2

hard gate
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ah dam

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didnt do the brackets

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alr all good thx

hard gate
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slender kraken
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You're given a word: "JJKKLM"

How many arrangements have “J” and “K” next to each other?

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@slender kraken Has your question been resolved?

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@slender kraken Has your question been resolved?

void nova
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Consider it as having the "letters" J, K, L, M, JK or the "letters" J, K, L, M, KJ. From this you subtract the intersection, which consists in those words formed with the "letters" L, M, JK, KJ

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Hence the answer will be:
5! + 5! - 4! which gives 216

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alpine vigil
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looks fine and correct

dire osprey
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is 16 cm the entire diagonal? (the green part)

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huh

pale cargo
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diagnols in a trapazoid are equal

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use trig

dire osprey
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the diagnols are equal yes

pale cargo
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trigonometry?

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oh

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oh okay

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fair

dire osprey
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i know trig but not how to use it here

pale cargo
dire osprey
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I mean you can't really figure out anything about the upper/down length and the height

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Not really

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you have to use diagnols for something

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damn it would be really convenient if anything else was given lmao

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I'm not really seeing any formula that revolves around using diagnoals to find a trapezoids area so I assume you sort of split it into other shapes

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but I kind of have no idea

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yeah

dire osprey
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I mean if the diagonals happen to be 90 degrees then obviously all the sides are 90 degrees

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"they will not form a right angle unless it is a right trapezoid"

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well this appearently is not a right trapezoid.

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I mean

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duh?

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the upper and lower length of a trapezoid must be parralel

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so that you can make a trapezoid

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in the first place

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i'm not sure how that helps lul

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runic spruce
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How’d they get the equation of the tangent

split swift
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the partial derivatives tell you two vectors that lie inside the plane (the ones with direction -12x and 89y), then the 50, 3 and 2 are from the point on the surface

runic spruce
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Thanks

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weak pelican
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how do you derive $e^{-10t}$

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weak pelican
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it should be e^-10t

fast peak
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put {} around the exponent in latex

weak pelican
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is that -10e^-10t ?

glossy valveBOT
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wakamole

weak pelican
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ty

fast peak
weak pelican
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is it $-10e^{-10t}$

glossy valveBOT
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wakamole

weak pelican
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ok so you move the sign

fast peak
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not sure what you mean

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you "move the -10 down"

weak pelican
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so in that case ... what if it is $v(t) = t^2e^{-10t}$

glossy valveBOT
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wakamole

fast peak
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product rule

weak pelican
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would it just be $2t(-10e^{-10t})$?

glossy valveBOT
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wakamole

weak pelican
fast peak
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no

weak pelican
fast peak
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do you not know what the product rule is?

weak pelican
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i dont know when to apply it

fast peak
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when you have a product of functions

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here, t^2 times e^(-10t)

weak pelican
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i think it is f(x(g) = f(x')(g) + f(x)(g')

weak pelican
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so i need to derive itby the equation i wrote?

fast peak
weak pelican
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ok i might as well show you the entire equation then.. it is $i(t) = C \frac{dv(t)}{dt}$ and C = 2

weak pelican
glossy valveBOT
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wakamole

weak pelican
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then it would be $2t^2e^{-10t}$?

glossy valveBOT
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wakamole

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wakamole

fast peak
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sry I have to go

weak pelican
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@fast peak so would i just put the 2 in front of the equation? or do that after?

weak pelican
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do you mind just answering that?

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@fast peak plz

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<@&286206848099549185>

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i have $v(t) = t^2e^{-10t}$, and $ i(t) = C\frac{dv(t)}{dt}$ so is the derivative of v(t) = $i(t) = C(2t)e^{-10t}+t^2(-10e^{-10t}$?

glossy valveBOT
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wakamole

weak pelican
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which equals $2(2te^{-10t}+t^2 *-10e^{-10t})$

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wakamole

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patent hamlet
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I'm struggling with part (ii) of this

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patent hamlet
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this is what i've done but that won't actually give me a matrix

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which is why I'm confused

leaden ermine
glossy valveBOT
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𝔸dωn𝓲²s

leaden ermine
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Other then that, L(1) and L(x²) look good

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torn jolt
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torn jolt
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im struggling

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how do i graph this

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from -3 to 4 its negative

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but how am i suppose to draw that if the only way it comes in from left to right is by increasing

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not decreasing

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question is asking for local max/min btw

sharp void
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to the left of -3, which is your local min, the function is actually decreasing

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it goes: decreasing on the left, going right it hits x = -3 and starts increasing, then when it hits x = 4 it starts decreasing again

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so you'd start graphing with something like this

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torn jolt
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Let T : R^3 -> R^3 be a Linear transformation with eigen values l1,l2,l3 and respective eigen vectors as (1,1,2) , (0,3,-1), (4,0,1l

Let x = (3,7,.5)

Find Tx

Could anyone please help me?

To find Tx

Should I write x as a Linear combination of the vectors given

After finding c1 (v1) + c2(v2)+ c3(v3)

T(x) = l1(c1 v1) + l2(c2 v2) + l3 (c3v3)

torn jolt
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Am I on the right track?

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Please help

kindred grove
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looks like a good plan yes

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@torn jolt

torn jolt
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I'm not sure how this gives the transformation though.

Do you by any chance know why we did this?

civic surge
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the transformation is linear right

torn jolt
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yes

civic surge
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so you can decompose your vector into many other vectors whose transformations are known

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and then add them up

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thats what your idea is

torn jolt
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Okay thank you so much both of you!

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cold sail
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cold sail
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this notation is confusin me a bit

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dont rly understand how they went from line 2 to line 3

torn gust
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like from D to the sums?
it's like (ud1+ud2+ud3)(ud1+ud2+ud3)f(a)

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smoky temple
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smoky temple
#

How am i supposed to solve this..

zealous wasp
#

Have you tried plugging in some values?

#

Cant read your righting, is that raised ot the power of 2 or e? and is the denominator e ?

smoky temple
#

This is it the question says calculate Dn

#

Would like to see what i did?

zealous wasp
#

Sure

smoky temple
zealous wasp
#

You still have to break them down into their prime factorization in terms of n I think

smoky temple
#

Yess but i couldn't calculate the gcd of n^2 and (n+2)^2

zealous wasp
#

Sorry, i m not sure how to manipulate the equation., i can see the answer because I wrote them down.

smoky temple
#

Ohh that's fine

torn jolt
smoky temple
torn jolt
#

ok

smoky temple
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smoky temple
#

No

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hoary belfry
#

Hey! May I ask for assistence for a Pre-Calculus problem that I'm stuck on? Below is the question and what I've done so far to solve the problem:

Question

Use trigonometric identities to find the solution of 2cos² (x) = 2sin² (x) + √2 in terms of integer k and the solutions in a single period [-π, π]. Give your answer in radians.
(Give your answer in the form of a comma-separated list if needed. Express numbers in exact form. Use symbolic notation and fractions where needed. Use k to represent any integer.)

What I've done so far

I have already gone ahead and solved the equation in two ways based on the Pythagorean identities for sin² (x) and cos² (x), but the reason I'm coming out today and asking this question is because of the result I got when solving for x:

# if using the identity `cos² (x)` => `1-sin² (x)`
x = arcsin(√((2-√2)/4))

OR

# if using the identity `sin² (x)` => `1-cos² (x)`
x = arccos(√((2+√2)/4))

What Im confused about is neither clearly look like a value that's on the unit circle, so I don't know what sort of angles these two values give back that are solutions to the equation above. I predict that they look similar to π/4 / 3π/4, but I have tried several answers on the period [-π, π] but I'm getting nowhere. I'm not sure on where to go from here, so I'm hoping someone can point out what I'm doing wrong/missing. Thanks!

hoary belfry
#

Here's the steps I took:

empty sapphire
#

you're very close!

#

but rather how about factoring out a 2 on both sides, then moving the sin^2(x) to the LHS and using a known trig identity

#

hint: I think you're knowledge with double when you use this identity

empty sapphire
#

yep, like this:

#

ignore the warning lol

#

then subtract sin^2(x)

#

then you have a known identity

hoary belfry
#

Ohh

#

wait

hard sigil
hoary belfry
#

But it would be cos^2(x) - sin^2(x)?

#

not plus?

empty sapphire
#

yep exactly

hard sigil
#

-a + b = b - a

hoary belfry
#

dang, gotta think about this. this seems like something I'd let slip by very easily

hoary belfry
#

Is this something related to even/odd ...?

hard sigil
#

not quite

hoary belfry
#

Double angle formula?

#

ohh

hard sigil
#

siiii

hoary belfry
#

So it'd be cos(2(theta)) = sqrt(2)/2, then use another formula for cos(2(theta)) to solve for x?

#

I think Im getting it

hoary belfry
#

okay, I'll try that out

#

thank you!

#

Would this be the answer?

hard sigil
hoary belfry
#

okay got it

#

If it's not then I'll keep working it out. Thanks for the help!

#

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torn jolt
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torn jolt
#

by subbing in these points

#

I've found the equations

#

$-15=a+b+c$

glossy valveBOT
#

Remlis

torn jolt
#

and

#

$45=9a-3b+c$

glossy valveBOT
#

Remlis

torn jolt
#

but I do know that the function has critical values of -3 and 1

#

$0=3x^2+2ax+b$

glossy valveBOT
#

Remlis

torn jolt
#

holon lemme try something

#

okay

#

so based on the roots being

#

(x+3)(x-1)

#

$c(x^2+2x-3)$

glossy valveBOT
#

Remlis

torn jolt
#

should be the resulting format

#

so therefore they are equal

#

"c" is a constanta

torn jolt
glossy valveBOT
#

Remlis

torn jolt
#

my question is

#

is it safe to assume here that c=3

#

that seems to have worked

#

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fair warren
#

not really sure how to solve this question

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@fair warren Has your question been resolved?

fair warren
#

<@&286206848099549185>

fossil stump
#

Triple integral, try using a diagram to help you visualize the solid

fair warren
#

my question is how to get the bounds for r

#

like i assume z is from sqrt(98-r) to sqrt(r^2) and

slate violet
glossy valveBOT
slate violet
fair warren
#

ahh

#

i got it thanks

#

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slate violet
#

Npnp

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ocean mist
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cerulean compass
#

what you finding man

ocean mist
#

x

cerulean compass
#

you heard of trig or nah

ocean mist
#

ya

cerulean compass
#

what ratio do you think this is

ocean mist
#

i’ve got a test tomorrow and i’ve been overthinking this so much

cerulean compass
#

you know double angles or no

ocean mist
cerulean compass
ocean mist
#

how would i answer it do i do 8 over sin29

cerulean compass
#

no

#

8sin29deg

ocean mist
#

ok this my problem pls help

cerulean compass
#

sin is opposite over hypotenuse

ocean mist
cerulean compass
#

okay you good?

ocean mist
#

so 3.87?

#

is that right

cerulean compass
#

lemme get my calculator

ocean mist
#

thanks so much

cerulean compass
#

its 3.88

ocean mist
#

yea

#

thank you sososo much

cerulean compass
#

remember to round corectly

ocean mist
#

thanks again

#

you’ve helped me a bunch

cerulean compass
#

do the .close command

#

when ur ready

ocean mist
#

.close

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white roost
#

Can someone tell me what are the other scenarios i got like nothing in mind

white roost
#

i also need help with this

#

this is my work

#

the thing here is i dont understand what the question is asking me

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limpid trail
#

consider the function ( f(x) = \frac{x^3 - 4x^2 + 5x - 2}{\sqrt{x+1}} )
determine all the x-values for which ( f(x) ) has a local maximum or minimum

getting stuck at handling the critical points

glossy valveBOT
#

SupaJay3

limpid trail
#

<@&286206848099549185>

reef pilot
#

Helping...

limpid trail
#

Tysm

#

I’m sleeping soon so if i dont reply when you post the solution dw i appreciate it yk?

#

Ty in advance though

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@limpid trail Has your question been resolved?

limpid trail
#

Sleeping now bye

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solemn fable
#

Given a prime number p > 3:
Prove that the above expression is divisible by p^3

solemn fable
#

I think im on the right path? but im stuck completely after this

pseudo cape
#

Maybe something with Fermat's little theorem

solemn fable
#

((p-1)!/k)^p + ((p-1)!/(p-k))^p = ((p-1)!/k(p-k))^p * (k^p + (k - p)^p)

solemn fable
#

kinda unlikely that the comp would give a question related to such

solemn fable
#

,, (\frac{(p-1)!}{k})^p + (\frac{(p-1)!}{p - k})^p = (\frac{(p-1)!}{k(p-k)})^p * (k^p + (k - p)^p)

glossy valveBOT
#

autism incarnated

solemn fable
#

Im thinking of using the choose function

#

cuz the k^p + (k-p)^p looking real good

#

<@&286206848099549185>

#

im so dead

#

ive been stuck on this for like an hour and a half

#

Ok yeah no i solved it

#

💀

#

solution surprisingly easy tbh

#

anyways

#

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sacred parcel
#

hello, i need help in topology.

if S1 x S1 = Tours = T
then what T x T = ?

vocal coyote
#

This space does not have an embedding in R^3

#

Do you need to know certain properties about this space?

#

What do you need to know about this space

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vocal coyote
#

@sacred parcel

#

Do you have a specific question about the space ?

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uneven ingot
#

I got kicked out fam

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uneven ingot
#

can anyone help me with this question

#

is this how u do the question

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#

@uneven ingot Has your question been resolved?

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#

@uneven ingot Has your question been resolved?

sacred rivet
#

why did the (5+cos 7x)^4 just suddenly jump to the numerator

#

also idk what youre doing with the f and g there

#

the whole blue RHS looks wrong

uneven ingot
#

Ohhhhh that’s why

#

Okay

#

So my logic was this

#

I forgot what this rule was called

#

I was doing this

sacred rivet
#

so it looks like youre trying to apply integration by parts

#

but it looks like you are applying basic integration rules wrong

#

the integral of (5+cos 7x)^4 is not 1/5 (5+cos 7x)^5

#

the power rule doesnt work like that

#

you should have learned chain rule by now

uneven ingot
#

Yes

#

Let me restart

#

I’m already wrong for, the start

sacred rivet
#

i mean

#

separation of variables is just basic algebraic manipulation

#

that part is correct

#

you can start at the step after youve separated variables

uneven ingot
#

Is LHS okay tho

#

Okay

sacred rivet
#

looks like a bad trig substitution?

#

how did you turn the sin^2 into some cos term

uneven ingot
#

Wait let me check if it’s even a thing 😢

#

Thisss

#

Oh wait

#

I forgot to times 2 the inside

sacred rivet
#

yeah

uneven ingot
#

Idk how sin^2 really works

#

I wanna clear up

#

Is it

#

(Sin(x))^2 = sin^2(x) =sin(x^2)

sacred rivet
#

the first two parts are correct

#

the last = sin(x^2) is not

#

this is one of those weird notation things in math where

#

sin is a function

#

and usually, when we superscript next to a function

#

like f^2(x)

#

it should mean f(f(x))

#

thats why f^-1(x) is the inverse, its like applying f negative 1 times

#

but trig functions are weird

uneven ingot
#

Hmm I get it

#

Matrix got similar feature

sacred rivet
#

for some reason we have decided that positive superscript is exponentiation of the entire term

uneven ingot
#

Oh

sacred rivet
#

so yeah once you understand that sin^2 x = (sin x)^2

#

the trig identities should make more sense

#

but these are honestly some really basic things to make mistakes on

#

it sounds like you got through a lot of math by muscle memory

uneven ingot
#

Ye

sacred rivet
#

and not really understanding the concepts behind what is happening

uneven ingot
#

I mean I know the sine waves and cosine waves

#

Signals in engineering but idk like basic basic

sacred rivet
#

so youll find yourself constantly making silly mistakes because you dont have an intuition for the rigorous rules

sacred rivet
#

i dont mind helping but there are a ton of knowledge gaps for me to fill

#

i dont want to like, alarm you or anything

#

after all, you got as far as you did kinda just blowing through

#

but my recommendation is to go back and review exactly how everything works

uneven ingot
#

Yep

sacred rivet
#

it will be massive help to you long term

iron plover
#

I would not take the disrespect

#

Me personally

sacred rivet
#

i dont mean it that way

iron plover
#

But yea hunni help me rq

sacred rivet
#

im sorry

iron plover
#

I’m joking

#

Lol

uneven ingot
#

Wait I have assignment

#

But I agree with cosmo

sacred rivet
#

but anyways @uneven ingot if you have any simple questions i can help but i really really recommend a review at some point

uneven ingot
#

I actually mostly memorise things and like practice but don’t know the meaning

sacred rivet
#

id love to help but like i said i am only one person

uneven ingot
iron plover
iron plover
sacred rivet
uneven ingot
#

Bottom right

#

Am I stuck in an infinite loop

#

Or am I unaware of some hidden tricks

#

Tbh I think I could expand the bracket and do sm about it

#

Can I?

sacred rivet
#

your g(x) is wrong

#

if you take the derivative, youll notice you do not get g'(x)

#

you should check your work more often

#

checking integrals is really easy because you can just take the derivative

uneven ingot
#

Ok

#

OHHHHHH

#

I rmb 😭

#

Wait 2 min approx

#

😭

uneven ingot
sacred rivet
#

yeah this is not looking good

#

now that youve tried the dead end

#

and you understand why its a dead end

#

ill steer you in the right direction

#

the integral from the beginning doesnt need integration by parts

#

it just directly uses chain rule, thats it

#

i had you try the dead end for practice and understanding

uneven ingot
#

😭 it’s 4am

#

okay

#

Wdym the integral from beginning

#

Like the start of the whole question?

#

Should I swap fx gx?

#

Seems like cool idea imma do that

#

Oh shit

sacred rivet
#

not the beginning

#

just the part where you did integration by parts

#

when you split f and g

uneven ingot
#

Doneeee

sacred rivet
#

double check it

uneven ingot
sacred rivet
#

and it should be good

#

take the derivative as usual

uneven ingot
#

Oh

sacred rivet
#

there are some bad habits in your work but we can leave that to some other time

uneven ingot
#

I was about to wolfram alpha

sacred rivet
#

dont until you have your own work

uneven ingot
#

Summarise it

sacred rivet
#

check using wolframalpha at the end

uneven ingot
#

I’ll note it

#

And change it

sacred rivet
#

because right now you need to get into good habits

#

and know what youre doing

#

overreliance on calculators at this point

#

is going to lead to more bad habits

uneven ingot
#

That’s true

#

I’m exploiting my calc so hard

#

It’s carrying my gpa literally

#

But I shouldn’t be doing that u are right

#

How did u know

#

That no need to do f and g

#

Can use u

#

Okay I admit I also skip a lotta steps

uneven ingot
#

Thank u so much

sacred rivet
# uneven ingot Imma sleep now ping and lmk when to use f and g and when to use u

its really difficult to give a good answer, basically, because there is no easy way to solve any integral. its almost entirely pattern recognition, and so thats why students who struggle with algebraic manipulation and arent comfortable doing them will struggle even harder, and why experience and practice is so important

chain rule states: d/dx f(g(x)) = d/dx f'(g(x)) g'(x)
(note that the above is written in a way that is slightly inaccurate technically, but i dont think youll notice and this might help you visualize the rule better)
in other words, as long as something looks like the form f'(g(x)) g'(x) then use chain rule

integration by parts is easier in one way but harder in another
product rule: (fg)' = f'g + fg'
integrate: fg = integral f'g + integral fg'
rearrange: integral f'g = fg - integral fg'
if the right side integral there is easier to solve, then apply integration by parts. in this way, its harder to see whether or not integration by parts would be useful to use, but nothing stops you from trying. when all of the easy methods (like chain rule) fail, sometimes i just turn a part of my brain off and just try integration by parts. if it doesnt work, try something else

#

so yeah, no good answer, but hopefully that helps

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lilac glacier
#

HELp

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glacial pasture
lilac glacier
#

<@&286206848099549185>

glacial pasture
#

any more info or is that it

#

ah, actually no its fine

#

what have you tried

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vapid pawn
#

Can smb tell me how is angle "42.3 or 127/3" coterminal with 120?

robust slate
#

42 1/3 is in radians

#

they're converting that to degrees

vapid pawn
#

Can't we simply have (x,y) as cos 42.pi/3 and sin 42.pi/3 instead of having them as cos 120 and sin 120?

robust slate
#

,w 254 mod 6

glossy valveBOT
robust slate
#

yeah

vapid pawn
robust slate
#

ignore that

vapid pawn
#

oh

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😭

#

alr ty again btw

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wait last thing, who's the owner of this server?

robust slate
#

idk

vapid pawn
#

alr who cares ig

#

.close

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#
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vapid pawn
#

Hol up

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How can 42 1/3 be in radians when 42 1/3 is a mixed number?

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.reopen

full forumBOT
#

vapid pawn
#

How can 42 1/3 be in radians when 42 1/3 is a mixed number tho?

limber forum
#

What's wrong with a mixed number having radians as its unit?

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Radians are dimensionless, you just have a number of them, could have 2 radians, pi radians, 0.000001 radians, 7/3 radians it's all chill

#

You can convert it into a single fraction if you prefer it that way lol

full forumBOT
#

@vapid pawn Has your question been resolved?

vapid pawn
#

Can u pls tell me a solution?

#

I tried plugging in 11pi/6 with "43 1/3" and still failed

limber forum
#

Probably cos it's not 120 degrees (edit: it is, when you contextualise it with the Q above, as elaborated on below lmao)

vapid pawn
#

lol

#

yea

#

Our mister may have made a mistake

#

I'll try to get everything checked.

#

And tysm again

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.close

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#
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vapid pawn
#

.reopen

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#

vapid pawn
#

Ill leave this ticket open though so if any1 else knows where's the problem and can reassure me

limber forum
#

Right I've read through your problem

#

Wrong wording, the 42 1/3 is right

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But that's telling you how many lots of 2pi go into your fraction

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So 42 lots remainder 1/3 lots of 2pi

vapid pawn
#

oh

#

So it's not supposed to be there?

limber forum
#

So that means you have 2pi/3 rads on the unit circle = 120 degrees

#

No it is that's fine

#

But you just need to use it correctly

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Take the remainder, multiply it by 2pi and that's how you get the angle on the unit circle

#

Then you can convert it to degs if you need to

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So 2pi/3 x 180/pi gives you the 120

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And hence the short way to do it is to just multiply the remainder by 360

vapid pawn
limber forum
#

But 42 1/3 is not 120 degrees in itself, it just is the route to getting 120 degrees

vapid pawn
#

So you mean

#

It would be the same as dividing 42 1/3 by "21 . 2pi"?

limber forum
#

Well your division is finding how many lots of 2pi radians go into the overall angle right

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So yeah

vapid pawn
#

OH ALR

#

TYTYTYTY

limber forum
#

When you divide it tells you 254pi/3 is equivalent to 42 x 2pi + 1/3 x 2pi (radians)

vapid pawn
#

ILY

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😭

limber forum
#

Np lol

full forumBOT
#

@vapid pawn Has your question been resolved?

vapid pawn
#

nvm

full forumBOT
#

@vapid pawn Has your question been resolved?

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#
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charred ore
#

so far ive yielded acd=3

#

not sure how to proceed

unique garnet
#

whats a c and d

charred ore
#

?

#

area of acd

unique garnet
#

oh

#

c is intersection of y=-3x+6 and y=mx+1 correct

charred ore
#

yep

#

<@&286206848099549185>

rustic pasture
#

Hint:What is the area of △BCD

charred ore
#

ummm not sure how i can even calculate that without the coordinates of c

rustic pasture
#

Sure △BCD=△ABO-?

charred ore
#

odca

#

oh wait

#

youre right

rustic pasture
#

Yes so you can compute the area of it

charred ore
#

i see

#

damm your intuition is so good

rustic pasture
#

Then you can get the ratio of AC:BC,It is equal to △ACD:△BCD

charred ore
#

thanks so much

#

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thick hedge
#

Let a variable line pass via the centre of $x^2+y^2-16x-4y=0$, meet the positive coordinate axes at points A and B, then find the minimum value of OA+OB where O is the origin

thick hedge
#

I found the general equation of the line

#

$\frac{x}{a}+\frac{y}{b}=1$

glossy valveBOT
#

ƒ(Why am. I here)=I don't know

#

ƒ(Why am. I here)=I don't know

thick hedge
#

It passes viapoint (8,2)

#

so we have

#

$\frac{8}{a}+\frac{2}{b}=1$

glossy valveBOT
#

ƒ(Why am. I here)=I don't know

thick hedge
#

here I suspect I have to use something like AM>GM>HM

#

am I right?

#

$\frac{8b+2a}{ab}=1$

glossy valveBOT
#

ƒ(Why am. I here)=I don't know

thick hedge
#

hmm

#

is this simply a calculus problem

#

assuming it is

#

ok, that makes it sort of doable

#

let the angle the line makes with the axis be $\theta$

glossy valveBOT
#

ƒ(Why am. I here)=I don't know

thick hedge
#

$\tan\left(\theta\right)\ =\frac{8}{2-l\cos\left(\theta\right)}$

glossy valveBOT
#

ƒ(Why am. I here)=I don't know

thick hedge
#

am I overcomplicating it

elfin stream
#

And remember that theta is between 90 deg and 180 deg

thick hedge
#

why must the hypotenuse be the radius

elfin stream
#

Its not an ellipse is it?

thick hedge
#

ah

#

got it

#

thanks

#

.close

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#
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elfin stream
#

@thick hedge nvm won't work

#

Cus the circle isn't centred at origin

#

I got a better approach

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elder storm
#

Help me Im struggling to find the missing parts of the triangle
This abt geometric mean theorem

dusky locust
#

You can find y via pythagorean theorem

#

w,z you can find because the triangles are similar

#

and x you add 16+w

elder storm
#

But tnx okokok

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sour torrent
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sour torrent
#

How do I know if the last inequality is true?

#

I used Leibniz

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@sour torrent Has your question been resolved?

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tame lark
full forumBOT
#
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
tame lark
#

1

neon geyser
tame lark
#

i dont know which law to use

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i know it law of cosines

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SSS

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but i dont know how to apply it

neon geyser
tame lark
#

no

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let me draw it rq

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alr done

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idk how to find angle B

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when i only have the formula to find angle A

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@neon geyser

neon geyser
tame lark
#

i prob drew it wrong but okay

tame lark
neon geyser
tame lark
#

alr-

#

what next

neon geyser
#

instead of using the formula (which you'll confuse yourself with)

#

think about the formula more abstractly

tame lark
#

a^2 + b^2 = c^2?

neon geyser
#

(the side opposite to b)^2 = (side1 adjacent to b)^2 + (side2 adjacent to b)^2 - 2 (side1 adjacent to b) (side2 adjacent to b) cos (angle B)

neon geyser
#

you can only use that when this triangle is right

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can u show that this triangle is not right?

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should be trivial ig

tame lark
#

uh i cant cause i have no angles

neon geyser
neon geyser
tame lark
#

wdym

neon geyser
#

lol which it does

#

😭

#

i thought u mentioned law of cosines

tame lark
#

how is it right

#

yea

neon geyser
#

,w 15^2 + (15*sqrt(3))^2

tame lark
#

dont you use law of cosines when you have all sides

neon geyser
#

you'd use law of cosines yeah

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but this is a right triangle

tame lark
#

ohhh

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so i did draw it wrong

neon geyser
#

well that's okay

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you're supposed to know by checking

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not by drawing

#

u said law of cosines and i saw 5 marks so i assumed it was law of cosines

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do you know what law of cosines is anyway?

tame lark
#

yeah

neon geyser
#

This thing?

tame lark
#

SAS or SSS

#

yeah i have that

neon geyser
#

Anyway yeah for your question it's fairly easy to see it's right

tame lark
#

cps A = b^2 + c^2 - a^2/ 2bc

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cos*

neon geyser
#

because it's a 30-60-90 triangle

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which i guess you're familiar with

tame lark
#

hmm alright

neon geyser
tame lark
#

how do you know those are the angles?

neon geyser
#

do you know 30-60-90 triangles?

#

or 45-45-90 triangles?

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they're special triangles

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the reason i know their angles is because of their side ratios

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x = 15

tame lark
#

hmm okay

#

ohhhh

#

ive seen this

#

so how would i explain i found angle B

neon geyser
#

why don’t you redraw your triangle first

tame lark
#

i already did

neon geyser
#

well you know immediately the answer is 60 degrees lol but yeah u can assume u don’t

#

okay now use sohcahtoa on angle b

tame lark
#

what is that

neon geyser
#

sin = opposite / hypotenuse

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cos = adjacent / hypotenuse

tame lark
#

oh ok

neon geyser
#

tan = opposite/ adjacent

tame lark
#

with the sides?

neon geyser
#

you abbreviate that to sohcahtoa

neon geyser
#

you can do anything really

#

sin(b), cos(b) or tan(b)

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oh wait your question wants you to use tan

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so use that

tame lark
#

how do i do that

neon geyser
#

draw the triangle inside the unit circle

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scale everything down by 30

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btw you wouldn’t have to do any of this

#

idk what your question means “use the unit circle”

tame lark
#

me neither

neon geyser
#

normally you’d just do tan(B) = opposite side/ adjacent side

tame lark
#

but what is the B

neon geyser
#

we don’t know

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but we do know opposite/ adjacent

tame lark
#

oh im dumb

neon geyser
#

i mean we do know but let’s assume we don’t lol

#

just send a pic of your new triangle

tame lark
#

so for part A

neon geyser
#

wait part A says determine m<B

#

u can just argue that this is a 30-60-90 triangle

#

and then show that angle B is then 60 by definition

tame lark
neon geyser
#

sin(B)

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not just sin

#

sin is a function

#

you need to feed it some input

#

same for cos and tan

tame lark
#

ok-

#

but what do i say for part A

#

angle B is 60 degrees by default?

neon geyser
#

well i don’t know what they want you to say

#

did you know the 30-60-90 thing before?

tame lark
#

yeah

neon geyser
#

okay then u can say that

tame lark
#

ill just explain why the triangle is a right angle

neon geyser
#

u first verified thag this triangle is right

tame lark
#

what did you tell me before

neon geyser
#

and then identified that it’s a 30-60-90 by looking at its side ratio

#

angle B is the angle opposite to the side 15sqrt(3)

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and in a 30-60-90 triangle, the angle opposite to xsqrt (3) has measure 60

neon geyser
tame lark
#

nothing you just explained it lol

#

what about for part b

neon geyser
tame lark
#

i cant send pictures in the question answer box thingy

neon geyser
#

and scale the sides of your triangle side down by 30

neon geyser
#

then what can u do? in that case they want you to use sentences?

tame lark
#

i have no idea

tame lark
#

im confused

neon geyser
#

i’m asking how u can submit your answer

#

do you write sentences or do you write answers or what’s going on?

tame lark
#

i have to like explain how i did it