Integrating x^2e^-3lnx: Tips and Tricks for Solving Tricky Integrals

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Homework Statement


int((x^2)(e^-3lnx))

anyone tips for this?

Homework Equations


The Attempt at a Solution

 
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Hint:

<br /> e^{-3 \, \ln{(x)}} = e^{\ln{(x^{-3})}} = ?<br />
 
Dickfore said:
Hint:

<br /> e^{-3 \, \ln{(x)}} = e^{\ln{(x^{-3})}} = ?<br />

now I get int (x^2)(e^(1/x^3)) then? stuck here
 
You are wrong. What does e^{\ln{y}} equal to? Use the property that the (natural) logarithm is the inverse function of the (natural) exponential function.
 
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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