A tuning fork is held a certain distance from your ears and struck. Your eardrums' vibrations after t seconds are given by p equals 9 sine 3t. When a second tuning fork is struck, the formula p equals 7 sine left parenthesis 3 t plus pi right parenthesis describes the effects of the sound on the eardrums' vibrations. The total vibrations are given by p equals 9 sine 3 t plus 7 sine left parenthesis 3 t plus pi right parenthesis. Complete parts (a)-(b).

Simplify p, the total vibrations, to a single term containing the sine