Answer to Question #274389 in Trigonometry for Mimi

Question

(e) Simplify a trigonometric expression sin θ cos² θ − sin θ

Answer 1

$$\sin \theta\cos^2\theta-\sin \theta=-\sin \theta(1-\cos^2\theta)$$

$$=-\sin \theta\sin^2 \theta=-\sin^3 \theta$$