How to write sin (x+y) - sin (x-y) as a product?

1 Answer
Konstantinos Michailidis
Feb 26, 2018

It is

sin(x+y)=sinxcosy+cosx*sinysin(x+y)=sinxcosy+cosx⋅siny

sin(x-y)=sinx*cosy-cosx*sinysin(x−y)=sinx⋅cosy−cosx⋅siny

Hence

sin(x+y)-sin(x-y)=2*cosx*sinysin(x+y)−sin(x−y)=2⋅cosx⋅siny

Related questions
Impact of this question
7695 views around the world
You can reuse this answer
Creative Commons License