Integrate x/sqrt(a^2+b^2-2abx)

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Homework Statement


I need to integrate x/sqrt(a^2+b^2-2abx) with respect to x.

The Attempt at a Solution


This follows from a substitution of the form x=cost in a textbook I'm reading - they jump to the solution straight from the above and I have no idea how to go about it - any hints will be very gratefully appreciated, thanks :)
 
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albega said:

Homework Statement


I need to integrate x/sqrt(a^2+b^2-2abx) with respect to x.

The Attempt at a Solution


This follows from a substitution of the form x=cost in a textbook I'm reading - they jump to the solution straight from the above and I have no idea how to go about it - any hints will be very gratefully appreciated, thanks :)

Hint: \int \frac{Au + B}{\sqrt u}\,du = \int Au^{1/2} + Bu^{-1/2}\,du.
 
pasmith said:
Hint: \int \frac{Au + B}{\sqrt u}\,du = \int Au^{1/2} + Bu^{-1/2}\,du.

Got it, thanks! Was that something you could spot or did you just know it from experience - I don't think I would ever have thought of something like that...
 
You also should make an attempt to post HW in the correct HW forum. There is a perfectly good Calculus-HW forum listed right below this one, which is where this post belongs.
 
SteamKing said:
You also should make an attempt to post HW in the correct HW forum. There is a perfectly good Calculus-HW forum listed right below this one, which is where this post belongs.

Thread moved to Calculus HH. :smile:
 
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