Question

Нужно доказать тождество

Answer 1

I hope this helps you

Answer 2

$2 + \frac{sin^4x+cos^4x}{sin^2xcos^2x} = \frac1{sin^2xcos^2x}\\2 + \frac{sin^4x+cos^4x}{sin^2xcos^2x} = \frac{sin^4x+2sin^2xcos^2x+cos^4x}{sin^2xcos^2x} = \frac{(sin^2x+cos^2x)^2}{sin^2xcos^2x} = \frac1{sin^2xcos^2x}$