*To*: mathgroup@smc.vnet.net*Subject*: [mg10492] Re[a + I b] = a*From*: Markus.Hetzenecker@uibk.ac.at (Markus Hetzenecker)*Date*: Tue, 20 Jan 1998 02:22:43 -0500*Organization*: University of Innsbruck, Austria

hallo how can I tell mathematica that the variable a and b is real, so that Re[a+ I b] results to a? or: n a integer number and Sin[n x] results to 0? I am using mathematica 2.2 thanxs, markus