Solving Integrals: q(x) on [0,1], xq(x), x^2q(x)

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Let q be a continuous function on [0,1] for which

Code:
\int_{0}^{1}q(x)dx=1

How do you solve the integrals

Code:
\int_{0}^{1}xq(x)dx

and

Code:
\int_{0}^{1}x^2q(x)dx

This is a real life (well, game theory) problem.
 
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Use tex tags instead of code tags and a \, like this (click on it)

\int_{0}^{1}x^2q(x)dx

The answer is, you don't. Just knowing the area under a curve doesn't determine either its first or second moments. You need more info.
 
That's too bad, but good to know. Thanks.
 
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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