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Re: Why all the if's the answer


aaronfude at gmail.com wrote:

>Suppose I start with :
>
>f = -Log[y*(1 + Cos[alpha])] + Log[(b*c - b*y + c*y*Cos[alpha] +
>Sqrt[b^2*(c - y)^2 + c^2*y^2 + 2*b*c*(c - y)*y*Cos[alpha]])/c];
>
>which I think is relatively innocent. I then integrate over y:
>
>Assuming[y > 0 &&  c > 0 && b > 0 && alpha > 0 && alpha < Pi/2,
>Integrate[y/c*f, {y, 0, c}]]
>
>After a few hours get a humongous answer with many If's, etc. What else
>can I assume or otherwise do to get an analytical answer?
>
>Many thanks in advance!
>
>Aaron Fude
>  
>
Try

Integrate[y/c*f, {y, 0, c}, GenerateConditions -> False]

This will return an answer much more quickly, but you will have to 
figure out whether the result is valid for the parameter ranges you are 
interested in.

Carl Woll
Wolfram Research


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