Can someone please help me derive the cos(alpha+beta) sin(alpha+beta)? Preferably in simple language X(
I have to be able to do this on a test tomorrow, please help me
PlanetMath: addition and subtraction formulas for sine and cosine
on one of the very back pages of googles. this is the same thing right?
i'm goign to ask a really stupid question sorry but...what is this used for?