Hi I just want to integrate analytically.

sqrt[(1/x)(exp(-x)-1)]

thanks in advance prasat

Hi, It isn't so easy for directly integration but you can write tylor series for exp(-x), I think in this way it will be simpler.

Yes I already did that it works very well from exp(-x)=1 nad exp(-x)=1-x after that when I substitute exp(-x)=1-x+0.5*x^2 I have diffculty in integrations. SQRT(3x-x^2) prasat

You can find it from mathematics handbook:you can chech this:

I= -x^.5/2*(3-x)^(3/2)+4/3*(3-x)^.5+2*(1/3^.5)*(ln(u)

U=(((3-x)^.5-3^.5)/((3-x)^.5+3^.5)))

Anyone with difficult integrals to evaluate (and that includes most of us at one time or another) should be aware of the classic text, "Tables of Integrals, Series and Products" by I. S. Gratshteyn and I. M. Rhyzhik. Originally translated from Russian, it is in its sixth edition (Aug 2002) and costs $79.95 from Elsevier. It was originally dirt cheap but is still a bargain. There is an older fifth edition from Academic Press for $99.95. (These prices from Barnes & Noble).