- #1
utkarshakash
Gold Member
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Homework Statement
Evaluate [itex]\displaystyle \int_0^{\pi} \log (1+a\cos x) dx[/itex]
Homework Equations
The Attempt at a Solution
Using Leibnitz's Rule,
F'(a)=[itex]\displaystyle \int_0^{\pi} \dfrac{\cos x}{1+a \cos x} dx [/itex]
Now, If I assume sinx=t, then the above integral changes to
[itex]\displaystyle \int_0^{0} \dfrac{dt}{1+a \sqrt{1-t^2}} [/itex]
Since both the limits are zero now, shouldn't the value of integral be 0!