sympy/sympy — pull request #1202 by manoj2378 (2012-04-04 09:22:55+00:00)
Title: Improved trigsimp for sin(x + y) and sinh(x + y)

calling trigsimp(sin(x+y) + sin(x-y)) would return 2*sin(x)*cos(y)
Added the same think for hyberbolic functions too