Ferrari
VIP
The only identity I remember is the half/double angle identities. and those don't apply if there isn't an addition sign.You can't pull out the constants A and B its part of the sin function, thats what i mean by you are gonna need some identities.
You have to rewrite it as sin(x)cos(2x) + cos(x)sin(2x) if we choose 3 as an arbitrary number..
But i did not take into account of the squared part of the equation which you would need to handle carefully

@Inquisitive_ take it away G.