Misbehavior of Conjugate[Exp[I x]]

*To*: mathgroup at yoda.physics.unc.edu*Subject*: Misbehavior of Conjugate[Exp[I x]]*From*: mek at guinan.psu.edu (Mark E. Kotanchek)*Date*: Tue, 2 Mar 93 16:42:07 -0500

Hi folks, Right now I'm swearing at mma because taking the conjugate of a complex exponential doesn't simplify much, i.e., In[35]:= Conjugate[Exp[I x]] Out[35]= I x Conjugate[E ] Ok, you say this is because "x" could be complex; however, if I load Algebra`ReIm` and define In[36]:= x /: Im[x] = 0 Out[36]= 0 I still get a result of In[37]:= Conjugate[Exp[I x]] Out[37]= I x Conjugate[E ] Now taking the Re[Exp[I x]] results in Cos[x] so mma at least understands that x is now defined to be real. Is there something I don't understand here or is this a deficiency in how mma handles (or doesn't handle) complex-valued equations. I'm also trying to do a series expansion of a complex-valued function of theta about theta = 0, Arg[rho[theta]]] wherein mma gives me answers involving the derivatives of "Arg". There may be subtleties here; however, I suspect that a major source of the problem is that mma is woefully deficient with respect to understanding domains. (Too bad Derive isn't available for the NeXT!) Any suggestions or comments? Grumble, mutter, etc., Mark. --- Mark Kotanchek Guidance & Control Dept - 363 ASB Applied Research Lab/Penn State P.O. Box 30 State College, PA 16804 e-mail: mek at guinan.psu.edu (NeXTmail) TEL: (814)863-0682 FAX: (814)863-7843