Integration of irrational function

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gruba
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Homework Statement


Find the integral [itex]\int \frac{1}{(x-2)^3\sqrt{3x^2-8x+5}}\mathrm dx[/itex]

2. The attempt at a solution
I can't find a useful substitution to solve this integral.
I tried [tex]x-2=\frac{1}{u},x=\frac{1}{u}+2,dx=-\frac{1}{u^2}du[/tex] that gives
[tex]\int \frac{1}{(x-2)^3\sqrt{3x^2-8x+5}}\mathrm dx=-\int \frac{u}{\sqrt{3\left(\frac{1}{u}+2\right)^2-8\left(\frac{1}{u}+2\right)+5}}\mathrm du[/tex]

Is there a useful substitution for [itex]u[/itex]?
 
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gruba said:

Homework Statement


Find the integral [itex]\int \frac{1}{(x-2)^3\sqrt{3x^2-8x+5}}\mathrm dx[/itex]

2. The attempt at a solution
I can't find a useful substitution to solve this integral.
I tried [tex]x-2=\frac{1}{u},x=\frac{1}{u}+2,dx=-\frac{1}{u^2}du[/tex] that gives
[tex]\int \frac{1}{(x-2)^3\sqrt{3x^2-8x+5}}\mathrm dx=-\int \frac{u}{\sqrt{3\left(\frac{1}{u}+2\right)^2-8\left(\frac{1}{u}+2\right)+5}}\mathrm du[/tex]

Is there a useful substitution for [itex]u[/itex]?
Factor ##\ 3x^2-8x+5\ ##. Then putting your u substitution into that simplifies things a bit.
 
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