Hello!
As I understand, we are speaking about
`int(sqrt(x/(x-1))-1)/x dx.`
We can omit the last term, -1/x, because we know its integral (ln|x|+C).
The remaining part is
`int sqrt(x/(x-1))/x dx=int 1/sqrt(x(x-1)) dx.`
Make some transformations with the function under integral, and assume that `xgt1:`
`1/sqrt(x(x-1))=1/sqrt(x(x-1))*(sqrt(x)+sqrt(x-1))/(sqrt(x)+sqrt(x-1))=`
`=(1/sqrt(x-1)+1/sqrt(x))/(sqrt(x)+sqrt(x-1))=`
`=2*((sqrt(x)+sqrt(x-1))')/(sqrt(x)+sqrt(x-1)).`
Now we can integrate it, because `int 1/u du=ln|u|+C:`
`int 1/sqrt(x(x-1)) dx = 2*ln(sqrt(x)+sqrt(x-1))+C.`
This is the answer for x>0 and without omitted `-ln(x).`
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