# Assuming and Conjugate do not work as expected [duplicate]

I tried to work with Conjugates in Mathematica and it did not produce my desired result. I learned about assumptions and figured they're my way to go. This is the code:

Assuming[Element[a, Reals] && Element[e, Reals] && Element[m, Reals] &&
Element[r, Reals] && e > 0 && r > 0 && m > 0, Conjugate[(a E^(-I Sqrt[2] Sqrt[e m] r))/r]]


However, this is the output:

(E^(I Sqrt[2] Conjugate[Sqrt[e m] r]) Conjugate[a])/Conjugate[r]


Since all variables are real and positive, I'd expect only the sign in the exponent to flip. Why does it still want to conjugate real positive variables?

## marked as duplicate by Jens, Bob Hanlon, MarcoB, happy fish, SzabolcsNov 9 '16 at 9:53

• Documentation for Assuming states clearly that it automates passing its argument to \$Assumptions, to be used by functions that have the Assumptions option. Conjugate is not such a function. But Simplify is such a function so you might try wrapping that around the expression to be altered. – Daniel Lichtblau Nov 8 '16 at 23:12