#what substitition do i do here

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forest graniteBOT
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placid ore
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U can use the property where u can replace x with 1-x

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Or try by parts

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or take x^2+1=t^2

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The third one is the best alternative imo

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Basically u wanna convert the root part into one variable

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So that u can seperate it

chrome yoke
placid ore
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When u cancel x^2 by 2x

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U get x/2

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So x can be root of t^2-1

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U should write this down and see where u get

sterile coral
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i was thinking of trig sub

placid ore
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That isn't necessary

sterile coral
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yeah nah probably overkill

placid ore
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Anyway hi

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Mikuroll

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;))

sterile coral
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๐Ÿ˜„

chrome yoke
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from x^2+1 = t^2

placid ore
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Whatever man u get the point

chrome yoke
placid ore
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Yes

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Ofc

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Or just take โˆš[x^2+1]=t

chrome yoke
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so 2x dx = 2t dt? like that?

placid ore
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Yes

chrome yoke
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t(t^2-1) dx

placid ore
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Are u sure that's what ur getting

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Also it should be dt

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Caus if that's it then just distribute and integrate

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But i doubt ur doing it right

chrome yoke
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i got โˆš[x^2+1]=t then
integral becomes x^2 t dx

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then i replace t with โˆš[x^2+1] ?

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but then i get x^2 โˆš[x^2+1]

placid ore
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Look

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U get t

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U have txdt

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X =โˆšt^2-1

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Simple u sub after that

chrome yoke
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dx = 2t/2x dt
then 2 cancel out
dx = t/x dt
x^2 t dx becomes
x^2 t * t/x dt

placid ore
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1+x^2)^1/2 becomes t

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Cancel x^2 with the x in denominator (dx=tdt/2x)

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So u have xt^2dt

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Converting x in terms of t

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U get t^2(t^2-1)^1/2

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Hmm

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Doesn't help at all

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How bout u replace x with 1-x

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And try to add and stuff

chrome yoke
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replace x with 1-x?

placid ore
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Yes it's a property in definite integrals

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Integral of f(x) from 0 to p= f(p-x) from 0 to p

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Another try..

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Take x^2 common out of root

sterile coral
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i think tan sub should be good

placid ore
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So u get x^3*(1+1/x^2)

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X^2 =t

sterile coral
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but im not thinking too hard

placid ore
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Now u get t*โˆš(1+1/t)dt

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Ok doesnt work either

placid ore
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Yep it does

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Bruh

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Fuck u ;)

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I tried too hard

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And u did it without thinking to hard

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Well once u did mention trig sub i thought I must do it without it lol

sterile coral
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i just do a lot of integrals

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it comes with practice

chrome yoke
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thanks guys @placid ore @sterile coral

knotty cypressBOT
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@chrome yoke has given 1 rep to @strong imp @sterile coral