Question

Упростить выражение (1/sin^2(x))-1

Answer 1

$\frac{1}{ sin^{2}x } - 1^{ (sin^{2}x } = \frac{1- sin^{2} x}{ sin^{2}x } = \frac{ cos^{2}x }{ sin^{2}x } = ctg^{2} x$