Cosα=- 25/24, 90° меньше α меньше 180° найдите sinα и tgα

[latex]cosa=-\frac{24}{25}\\\\90^\circ\ \textless \ x\ \textless \ 180^\circ\; \; \to \; \; sina\ \textgreater \ 0\; ,\; \; tga\ \textless \ 0\\\\sina=+\sqrt{1-cos^2a}=\sqrt{1-\frac{24^2}{25^2}}=\frac{7}{25}\\\\tga=-\sqrt{\frac{1}{cos^2a}-1}=-\sqrt{\frac{25^2}{24^2}-1}=-\sqrt{\frac{49}{574}}=-\frac{7}{24}[/latex]