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azatkgz
Oct7-07, 08:15 AM
1. The problem statement, all variables and given/known data

\int\frac{x^3dx}{\sqrt{2-x}}




3. The attempt at a solution
I solved it in this way
for v=2-x
\int-\frac{(2-v)^3dv}{\sqrt{v}}=-\int\frac{(8-12v+6v^2+v^3)dv}{\sqrt{v}}
=-\int\frac{8dv}{\sqrt{v}}+\int 12\sqrt{v}dv-\int 6v\sqrt{v}dv-\int v^2\sqrt{v}dv
is it true?
Is there any other methods?

neutrino
Oct7-07, 09:47 AM
That's one way of doing it. If you substitute v2 for 2-x, you will have a radical-free expression to integrate.

azatkgz
Oct7-07, 09:55 AM
Ok,very nice.