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1. Integration help!
I'm quite stuck on this

1
______________ dx

(1-x^2)^1.5)

Substitution is x=sinθ and the limits given are 0.5 and 0

2. Re: Integration help!
(Original post by The Hedonist)
I'm quite stuck on this

1
______________ dx

(1-x^2)^1.5)

Substitution is x=sinθ and the limits given are 0.5 and 0

1/(cos^2theta)^1.5 go from there . Also remember to change the limits.
Last edited by Deep456; 06-03-2012 at 17:52.
3. Re: Integration help!
Well what have you tried? Certainly that substitution looks like a good idea.
4. Re: Integration help!
(Original post by Deep456)
1/(cos^2theta)^1.5 go from there . Also remember to change the limits.
but surely:

so

so the integral would be
Last edited by just george; 06-03-2012 at 18:05.
5. Re: Integration help!
(Original post by just george)
but surely:

dx/dtheta = cos(theta) so dx = cos(theta) dtheta

so the integral would be cos(theta) / (cos^2theta)^1.5 dtheta
All I have done is subbed in sin theta and used the identity. I haven't done anything else.

What you have done is also correct ,yes.
Last edited by Deep456; 06-03-2012 at 18:00.
6. Re: Integration help!
(Original post by Deep456)
All I have done is subbed in sin theta and used the identity. I haven't done anything else.
sorry yeah it just looked a bit misleading to me, looked like you were saying the integral was

The Hedonist - basically just use the substitution given, remember to change between dx and dtheta, the limits, and then hopefully you will be left with something you can integrate
Last edited by just george; 06-03-2012 at 18:08.