Q) Express 3 sin x + 4 cos x in the form R cos (x-a) a is alpha
any idea i think we must change the sinx into cos x This problem
can easily be solved my comparing coefficients. First start by
stating your identity. It is important that you understand
exactly what means before you go ahead, if you don't just say.
Expand the left hand side using the compound angle formula.
compare coefficients to get do you want to try and finish off
form here ? let me know how it goes form here. If two
expressions are identical then the coefficients and respectively
are the same. the coefficient of on the left hand side is and on
he right hand side it is 3. are you following ?