Question

4 multiple choice 1 point evaluate the trigonometric function of the given quadrantal angle. $\cos\frac{13\pi}{2}$ 1 0 undefined -1

Explanation:

Step1: Simplify the angle

Subtract \(2\pi\) (a full - rotation) from \(\frac{13\pi}{2}\) multiple times.
\(\frac{13\pi}{2}-6\pi=\frac{13\pi - 12\pi}{2}=\frac{\pi}{2}\)

Step2: Use the cosine function value

We know that the cosine function \(y = \cos x\) has the property \(\cos(x + 2k\pi)=\cos x\) for any integer \(k\).
For \(x=\frac{\pi}{2}\), \(\cos\frac{\pi}{2}=0\)

Answer:

B. 0