Rewrite as a single expression. cos(10$\theta$)cos(6$\theta$ ) - sin(10$\theta$ )sin(6$\theta$ )
A) cos(16$\theta$)
B) cos(4$\theta$ )
C) sin(16$\theta$ )
D) sin(4$\theta$ )

Question

Quizplus · Accepted Answer

We can use the trigonometric identity cos(a-b) = cos(a)cos(b) + sin(a)sin(b) to rewrite the given expression as cos(10F1F1F1S1F1F1F10 - 6F1F1F1S1F1F1F10), which simplifies to cos(16F1F1F1S1F1F1F10). Therefore, the best choice is A.

Rewrite as a Single Expression θ\thetaθ )Cos(6 θ\thetaθ ) - Sin(10 θ\thetaθ )Sin(6 θ\thetaθ

Rewrite as a Single Expression $\theta$ )Cos(6 $\theta$ ) - Sin(10 $\theta$ )Sin(6 $\theta$