Revisiting Repeated Integrals: A Challenging Problem in Integration

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Homework Statement



Evaluate the following repeated integral:

\int^2_0 dv \int^\frac{1}{2}_0 \frac{v}{\root(1-u^2) du}


The Attempt at a Solution



since 1/something is something ^(-1), and root something is something^(1/2), i rearragned to get..


\int^2_0 dv \int^\frac{1}{2}_0 1 - u^2)^\frac{1}{2} du}

integrating using standard integral

(ax+b)^n = \frac{(ax+b)^{n+1}}{a(n+1)}

\int^2_0 [ \frac{(1 - u^2)^{1/2}}{-1(\frac{v}{2})}

which i solved to get.

\int^2_0 -\frac{2(\frac{3}{4})^{3/4}}{v} dv<br />

given that the answer in the book is pi over 3, i think I've made a mistake (also that 3/4 ^ 3/4 doesn't look right since surley it won't resolve well?)
 
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The inner integral is not a linear function of the dependent variable ie, it is not of the form (ax+b)^n, it is more like (ax^2+b)^n. In your case, there is a very simple answer for the integral you seek. Check your integration tables or better still, come up with the solution on your own.
 
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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