Question

Select the best answer.

sin(3pi/3 + x) =

• sinx
• -sinx
• -cosx
• cosx

Answer 1

-sin x

Explanation:

sin(3π/3+x)=sin (π+x)=-sin x

or

sin (π+x)=sin πcos x+cos π sin x=(0)cos x+(-1)sin x=0-sin x=-sin x