Verified Answer :

LammettHash

\(3\cos x=0\implies \cos x=0\)

This happens when \(x\) is an odd multiple of \(\dfrac\pi2\), and there are four instances of this happening in the given interval: \(\pm\dfrac\pi2,\pm\dfrac{3\pi}2\).

SociometricStar

Answer:

\(x=-\frac{3\pi}{2},\frac{\pi}{2},\frac{\pi}{2},\frac{3\pi}{2}\)

Step-by-step explanation:

We have to find the zeros of the function f(x)=3cosx at  [-2pi,2pi]

For zeros, we have f(x) = 0

\(3\cos x=0\)

Divide both sides by 3

\(\cos x=0\)

The value of cos is zero at \((2n+1)\frac{\pi}{2}\)

Hence, in the interval [-2pi,2pi], the value of x should be

\(x=-\frac{3\pi}{2},\frac{\pi}{2},\frac{\pi}{2},\frac{3\pi}{2}\)