Question

Вычислите tg a и sin a?tckb cosa=-3\5 и п а 3п/2

Answer 1

$cos \alpha =- \frac{3}{5}\\\\\pi \ \textless \ \alpha \ \textless \ \frac{3\pi }{2}\quad \Rightarrow \quad sin \alpha \ \textless \ 0\; ,\; \; tg \alpha \ \textgreater \ 0\\\\sin \alpha =-\sqrt{1-cos^2 \alpha }=-\sqrt{1- \frac{9}{25}}=- \frac{4}{5}\\\\tg \alpha = \frac{sin\alpha }{cos\alpha }=\frac{-4/5}{-3/5}= \frac{4}{3}$