# Understanding compund angle formulas

by zeion
Tags: angle, compund, formulas
 HW Helper P: 3,535 In the case of the formulae such as $$sin(A+B)=sinAcosB+cosAsinB$$ it is much easier and definitely quicker to memorize than to reproduce in an exam. But I prefer to reproduce the cofunction identities than to memorize them because they are easy to do so, which you might as well. I think it's just best to memorize these formulae.