Question

Упростите:

$\frac{sin t-1}{cos t} * \frac{sin t+1}{cos t}$

Answer 1

ОДЗ: cost≠0

$\frac{sint-1}{cost} * \frac{sint+1}{cost}= \frac{sin^{2}t-1 }{ cos^{2} t} = \frac{- cos^{2} t}{ cos^{2} t} =-1$