Intergration problem

  • Thread starter miller8605
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  • #1
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Homework Statement


i'm taking a defitinite integral from sqrt2 to 2 of the function 1/x^3*sqrt(x^2-1)dx.

Homework Equations





The Attempt at a Solution


I seperated it into 1/x^3 and 1/sqrt(x^2-1). I have the second part using trig sub. as being sec theta dtheta, before integrating it. I believe i did this part correctly.

What I can't remember is that I make 1/x^3 to x^-3 and then integrate it that way with the final being -1/2(1/x^2)??

Am i going about this correctly?
 

Answers and Replies

  • #2
Tom Mattson
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I seperated it into 1/x^3 and 1/sqrt(x^2-1).

No need to do that. The entire integrand comes out very nice with a trig substitution.

I have the second part using trig sub. as being sec theta dtheta, before integrating it. I believe i did this part correctly.

The part in red makes very little sense to me, but it sounds like it has the kernel of a correct method in there. Could you elaborate?
 

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