Use an identity to write the expression as a single trigonometric function or as a single number.
-$\cos \left( \theta + \frac { \pi } { 2 } \right)$
A) $- \sin \theta$
B) $- \cos \theta$
C) $\sin \theta$
D) $\cos \theta$

Question

Quizplus · Accepted Answer

The identity for $\cos(\theta + \frac{\pi}{2})$ is $-\sin(\theta)$, which comes from the co-function identity involving cosine and sine.

Use an Identity to Write the Expression as a Single cos⁡(θ+π2)\cos \left( \theta + \frac { \pi } { 2 } \right)cos(θ+2π​)

Use an Identity to Write the Expression as a Single $\cos \left( \theta + \frac { \pi } { 2 } \right)$