Different results for same integration

*To*: mathgroup at smc.vnet.net*Subject*: [mg72964] Different results for same integration*From*: "ashesh" <ashesh.cb at gmail.com>*Date*: Fri, 26 Jan 2007 07:42:42 -0500 (EST)

Hi all, I am trying to do the following two integrations, which are basically the same, but with a change of variable. I am getting different results from both of them. Hope some one can point out the mistake I am making. a = 19.0; b = 4.0; t = 5.0; Integrate[(a + b)/Sqrt[(a^2 - x^2)*(b^2 - x^2)], {x, b, b + I*t}] Integrate[(1 + b/a)/Sqrt[(1 - y^2)*(1 - (b^2*y^2)/a^2)], {y, 1, (b + I*t)/b}] where y = (x/b) The first integration gives: -1.23787 + 1.44831 I while the second one gives: 6.17818 - 5.4757 I The upper limits of the integrations are complex (b + i t) and ((b + i t)/b) respectively. The result from the first integration is correct and I have verified it analytically. Looking forward for any help in resolving the problem. Ashesh

**Follow-Ups**:**Re: Different results for same integration***From:*leigh pascoe <leigh@cephb.fr>