Use the fundamental identities to simplify the expression.
-$\cos \theta - \cos \theta \sin ^ { 2 } \theta$
A) $\sin \theta$
B) $\cos ^ { 3 } \theta$
C) $\sec ^ { 2 } \theta$
D) $\tan ^ { 2 } \theta$

Question

Quizplus · Accepted Answer

The expression can be simplified using the Pythagorean identity $\sin^2 \theta + \cos^2 \theta = 1$, which allows us to rewrite $\cos \theta - \cos \theta \sin^2 \theta$ as $\cos \theta (1 - \sin^2 \theta)$. Using the identity again, $1 - \sin^2 \theta = \cos^2 \theta$, so the expression simplifies to $\cos \theta \cos^2 \theta = \cos^3 \theta$.

Use the Fundamental Identities to Simplify the Expression cos⁡θ−cos⁡θsin⁡2θ\cos \theta - \cos \theta \sin ^ { 2 } \thetacosθ−cosθsin2θ

Use the Fundamental Identities to Simplify the Expression $\cos \theta - \cos \theta \sin ^ { 2 } \theta$