Trig identity for linear combination of sines

*To*: mathgroup at smc.vnet.net*Subject*: [mg100814] Trig identity for linear combination of sines*From*: Chelly <chelly85086 at gmail.com>*Date*: Sun, 14 Jun 2009 21:20:41 -0400 (EDT)

Hi: I have a function which is a linear combination of sines, of the form y = a*sin(x+q) + b*sin(x+r) + c*sin(x+t) and I am looking for a trignometric identity that would reduce the above to the form y = A*sin(x+Z) I would also like to find out how to implement this rule in Mathematica. Thanks Chelly

**Follow-Ups**:**Re: Trig identity for linear combination of sines***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>