Integration Help: dx/(5-4x-(x^2))^(5/2)

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Homework Statement



Hi everyone
im stuck with the following integration..

Homework Equations



integral of dx/(5-4x-(x^2))^(5/2)

The Attempt at a Solution



can anyone help me?
thanks
 
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… complete the square … !

Hi joseph! :smile:

With quadratics, it's usually best to start by completing the square:

5 - 4x - x^2 = 9 - (x + 2)^2.

(And then you can even change to y = x + 2, dy = dx, if you like!)

Does that help? :smile:
 
OH YEAH!
i never thought of that!
thanks alot!
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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