\(\int \frac 1{\sin^2x\cos^2x}dx\)
\(= \int \frac{sin^2x + cos^2x}{sin^2x\cos^2x} dx\) (Using sin2x + cos2x = 1)
\(= \int \frac{\sin^2x}{\sin^2x \cos^2x}dx + \int \frac {\cos^2 x}{\sin^2x\cos^2x}dx\)
\(= \int \frac 1{\cos^2x} dx + \int \frac 1{\sin^2x}dx\)
\(= \int \sec^2x dx + \int cosec^2x\, dx\)
\(= \tan x - \cot x + C\)