Question

Evaluate: $\int \frac{dx}{({\cos }^{2}x/2-{\sin }^{2}x/2{)}^2}$

Answer 1

$\int \frac{dx}{({\cos }^{2}x/2-{\sin }^{2}x/2{)}^2}\int \frac{dx}{co{s}^{2}x}\int {\sec }^{2}xdx\tan x+c$