Sin(35pi/2 - x) + cos(68pi - x) =? Сократить

Question

Sin(35pi/2 - x) + cos(68pi - x) =?
Сократить

Answer 1

Sin(35π/2-x)=sin(3π/2-x)=-cosx
cos(68π-x)=cosx
-cosx+cosx=0