Question:
Mark (√) against the correct answer in the following:
Let $f(x)=\sqrt{\cos x}$. Then, dom $(f)=?$
A. $\left[0, \frac{\pi}{2}\right]$
B. $\left[\frac{3 \pi}{2}, 2 \pi\right]$
C. $\left[0, \frac{\pi}{2}\right] \cup\left[\frac{3 \pi}{2}, 2 \pi\right]$
D. none of these
Solution:
$f(x)=\sqrt{\cos x}$
As per the diagram
We can imply that domain of $\sqrt{\cos x}$
is $\left[0, \frac{\pi}{2}\right]\left[\frac{3 \pi}{2}, 2 \pi\right]$