Help Mathematica simplify this

*To*: mathgroup at smc.vnet.net*Subject*: [mg111069] Help Mathematica simplify this*From*: Sam Takoy <sam.takoy at yahoo.com>*Date*: Mon, 19 Jul 2010 02:09:37 -0400 (EDT)

Hi, For some reason Mathematica fails to do this: Assuming[ a Cosh[H/(2 a)] == 1, FullSimplify[ Cosh[H/a] + 1/2 ((H/a - H/a Cosh[H/a] + 2 Sinh[H/a]) Sinh[H/(2 a)] )/( H/(2 a) Sinh[H/(2 a)] - 1/a)]] The answer is actually 1 and I would think Mathematica could handle that. Is there a way to fix this? (This is a warmup for me more complicated problems.) Thanks!