The number of critical points of the function f(x)= {|(sin x)/x|, x ≠ 0; 1, x=0} in the interval (-2 π, 2 π) is equal to:

The number of critical points of the function $\displaystyle f(x)=\left\{\begin{array}{ll}\left|\frac{\sin x}{x}\right| & , x \neq 0 \\ 1 & , x=0\end{array}\right.$ in the interval $\displaystyle (-2 \pi, 2 \pi)$ is equal to :