Question

I need a little help on this question of Trig, I will attach a picture.

Answer 1

You need to apply associative angles' formula here. Do you know the formulae?

Answer 2

sin(a+B)= sinAcosB +cosAsinB
sin (A-B)= sin A cosB-cosAsinB
cos (A+B)=cos AcosB-sinAsinB
tan(A-B)=(tanA-tanB)/(1+tanAtanB)

Apply them

Answer 3

Ohhh okay I got it now duh thanks!

Answer 4

P.S.: This wasn't a college question, why did you tag it as one?

Answer 5

I didn't mean to.