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Quick Question - Integration

I'm trying to integrate x(x1)12dx\int \frac{x}{(x-1)^{\frac{1}{2}}} dx

So I said Let u=x1u=x-1 so x=u+1x=u+1 and dudx=1du=dx\frac{du}{dx}=1 \rightarrow du=dx

Therefore u+1u12dx(u12+u12)dx23u32+2u12+C\int \frac{u+1}{u^{\frac{1}{2}}} dx \rightarrow \int (u^\frac{1}{2}+ u^{-\frac{1}{2}}) dx \rightarrow \frac{2}{3}u^{\frac{3}{2}}+ 2u^{\frac{1}{2}} +C

Then when subbing u back in 23(x1)32+2x1+C\frac{2}{3}(x-1)^{\frac{3}{2}}+2\sqrt{x-1}+C

Whereas the answer is suppose to be 23(x+2)x1+C\frac{2}{3}(x+2)\sqrt{x-1} +C

What am I doing wrong?
Reply 1
Take out the common factor of x1\sqrt{x-1} in your answer, you should end up with what the book says.
yh
Reply 3
DFranklin
Take out the common factor of x1\sqrt{x-1} in your answer, you should end up with what the book says.

Thanks Got it!

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