Question

Rewrite as a sum or difference
sin(3t)sin(5t)

Answer 1

Anyonneee?

Answer 2

I'm not sure what exact answer you are looking for, but here is something that involves a difference:

Let A=3t
Let B=5t

Since cos(A-B)=(cosA)(cosB)+(sinA)(sinB)
Then (sinA)(sinB)=cos(A-B)-(cosA)(cosB)
and sin(3t)sin(5t)=cos(3t-5t)-cos(3t)cos(5t)