Solving Indefinite Integrals: "int (1/(sqrt -x^2 -2x))dx

Thread starter Atilla1982
Start date Nov 15, 2005
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Indefinite Indefinite integral Integral

Nov 15, 2005

Atilla1982

I have:

int (1/(sqrt -x^2 -2x))dx

so I rewrite (-x^2-2x) --> 1-(x+1)^2 and swap those two.

then I say t=x+1, and substitute that in.

So now I have:

int (1/(sqrt 1-t^2)) dt

Here I get stuck, can anyone please help?

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Nov 15, 2005

hypermorphism

That was an excellent substitution. Review the derivative of the arcsine function.

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