Number of solution of $2^{\sin|x|}=4^{|\cos x|}$ in [− π, π] is equal to _____.

4

The total number of solutions of the given equation is equal to the number of points of intersection of curves $y=4^{|\cos x|}$ and $y=2^{\sin|x|}$. Clearly, these two curves intersect at four points. So, there are four solutions of the given equation in the interval [-π, π].