Question

2sin^2x*ctgx нижняя дробь
cos^2x-sin^2x

Answer 1

$frac{2Sin ^{2}xCtgx }{Cos x^{2}x-Sin ^{2}x } = frac{2Sin x^{2} x* frac{Cosx}{Sinx} }{Cos2x} = frac{2SinxCosx}{Cos2x} = frac{Sin2x}{Cos2x}=tg2x$