Recall the compound angle formulae:
sin(A+B) = sinAcosB + cosAsinB
cos(A+B) = cosAcosB - sinAsinB
sin(A+B) + cos(A+B) = sinAcosB + cosAsinB + cosAcosB - sinAsinB
I think?? It looks a little too complicated to be the answer though
(Btw this is Math haha why is this question under English)
