Question

СРОЧНО!!! ДАЮ 80 балов
На фото

Answer 1

Ответ:

$\displaystyle -\frac{12}{25}\\\\\frac{12}{25}$

Объяснение:

$\displaystyle sin^2\alpha+cos^2\alpha=1\\\\\left(\frac{3}{5}\right)^2+cos^2\alpha=1\\\\\frac{9}{25}+cos^2x=1\\\\cos^2\alpha=1-\frac{9}{25}\\\\cos^2\alpha=\frac{16}{25}\\\\cos\alpha=-\sqrt{\frac{16}{25}}\\\\cos\alpha=-\frac{4}{5}\\\\\\sin2\alpha=2sin\alpha cos\alpha=\frac{3}{5}\cdot(-\frac{4}{5})=-\frac{12}{25}$

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$\displaystyle sin^2\alpha+cos^2\alpha=1\\\\sin^2\alpha+\left(-\frac{4}{5}\right)^2=1\\\\sin^2\alpha+\frac{16}{25}=1\\\\sin^2\alpha=1-\frac{16}{25}\\\\sin^2\alpha=\frac{9}{25}\\\\sin\alpha=-\sqrt\frac{9}{25}\\\\sin\alpha=-\frac{3}{5}\\\\\\sin2\alpha=2sin\alpha cos\alpha=-\frac{4}{5}\cdot(-\frac{3}{5})=\frac{12}{25}$