Question

Упростите: $frac{cos^{2} -1 }{sin^{2} -1}$ !!SOS!!

Answer 1

$frac{cos^2x-1}{sin^2x-1}= frac{-(1-cos^2x)}{-(1-sin^2x)}= frac{sin^2x}{cos^2x}=tg^2x$