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SoulSearcher

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I take it you don't know integration by parts? Well, if I remember correctly, the indefinite integral of sin-1x is xsin-1x + sqrt(1-x2) + constant, usually they would give a sort of a lead in question to help you find the integral of arcsin x, since I dont think that it is possible to integrate it directly using extension 1 methods.
 
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last time i heard 3u people didnt have to integrate inverse trig.

but if you're talking about area under a inverse trig curve. just convert it normal trig and change the limits.
 

JasonNg1025

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yeah integration by parts should work

let's try

(I use arcsin(x) for inverse sine)

I = int(arcsin(x)dx)

u = arcsin(x), dv = dx.
du = 1/(sqrt(1-x^2)) (dx), v = x

I = xarcsin(x) - int(x/(sqrt(1-x^2)))

use substitution u = 1-x^2

if you multiply the integral by -1/2 you get a -2x up the top

and you just get -int(1/sqrt(u)du) which should be easy enough

hope it's not too hard to read

(this is if you havn't managed to do it yet :) )

and I thought integration by parts was in the extension 2 course... so if you just do extension 1 I'd leave it

and oh wow you actually remembered it? :confused:
 

SoulSearcher

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the-1-n-only-me said:
last time i heard 3u people didnt have to integrate inverse trig.

but if you're talking about area under a inverse trig curve. just convert it normal trig and change the limits.
If that was the case, it'd be a lot easier to do that than memorise the integral of arcsin x.
JasonNg1025 said:
and oh wow you actually remembered it? :confused:
After doing the question a few times it just stuck in my head.
 
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Chinmoku03

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IIRC, an inverse sine curve is just a sine curve about the y axis, so you can use the V = pi x Sx2dy, where S is the integration symbol, cos I dunno where to find one >.>;
 
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Buiboi

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Chinmoku03 said:
IIRC, an inverse sine curve is just a sine curve about the y axis, so you can use the V = pi x Sx2dy, where S is the integration symbol, cos I dunno where to find one >.>;
OOOOHHHHHH YEAH!!...i remember using this way to do it b4...

CHEERS!
 

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