Re: Why all the if's the answer

*To*: mathgroup at smc.vnet.net*Subject*: [mg70800] Re: [mg70783] Why all the if's the answer*From*: Carl Woll <carlw at wolfram.com>*Date*: Sat, 28 Oct 2006 05:21:37 -0400 (EDT)*References*: <200610270428.AAA24487@smc.vnet.net>

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

**References**:**Why all the if's the answer***From:*aaronfude@gmail.com