Question

How do you prove `9sin(3x)cos(3x)`?

Answer 1

`(9/2)sin(6x)`

Explanation:

we know that

`2sin(x)cos(x)=sin(2x)`

then:

`9sin(3x)cos(3x)=(9/2)*2sin(3x)cos(3x)`

`(9/2)sin(6x)`