For what valve of k is the following function

For what valve of $k$ is the following function

$f(x)=\left\{\begin{array}{c}\frac{k \cos x}{\pi-2 x}, \text { if } x \neq \frac{\pi}{2} \\ 3, \text { if } x=\frac{\pi}{2}\end{array}\right.$ is continuous at $x=\frac{\pi}{2}$

Ans. $k=6$