Re: RE: Bug in math4
- To: mathgroup at smc.vnet.net
- Subject: [mg20703] Re: [mg20662] RE: [mg20633] Bug in math4
- From: BobHanlon at aol.com
- Date: Mon, 8 Nov 1999 02:48:46 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Ted, Re: Integrate[Sqrt[2-Sin[x]],{x,1,Pi/2,4}] I cannot find any documentation in the on-line Help nor at http://www.dot.net.au/~elisha/ersek/Tricks.html for use of the additional (third of four) argument in the iterator in Integrate (Pi/2 in this case). What is this argument doing and where is its use documented? Thanks, Bob Hanlon In a message dated 11/7/1999 6:22:40 AM, ErsekTR at navair.navy.mil writes: >Lennart Bengtsson indicated the problem discussed earlier might be at >x=Pi/2. Below we see this is the case. I don't know I didn't make the >connection between 1.57... and Pi/2 earlier. > > >In[1]:= >Integrate[Sqrt[2-Sin[x]],{x,1,4}] > >Out[1]= (*** Wrong answer ***) >-2*EllipticE[(-4 + Pi/2)/2, -2] + > 2*EllipticE[(-1 + Pi/2)/2, -2] + > 4*EllipticF[I*ArcSinh[1/Sqrt[2]], -2] > > >In[2]:= >Integrate[Sqrt[2-Sin[x]],{x,1,Pi/2,4}] > >Out[2]= (*** Right answer ***) >-2*EllipticE[(-4 + Pi/2)/2, -2] + >2*EllipticE[(-1 + Pi/2)/2, -2] >