Question

Sinβ+2 sin5β+ sin9β <--Express as a product Can someone help with this?

Turn that into something combined basically

Answer 1

`sinbeta+2sin5beta+sin9beta`

`=sinbeta+sin5beta+sin5beta+sin9beta`

`=2sin3betacos2beta+2sin7betacos2beta`

`=2cos2beta(sin3beta+sin7beta)`

`=2cos2beta(2sin5betacos2beta)`

`=4cos2betasin5betacos2beta`