Question

СРОЧНО!!!овлвлыллвлв​

Answer 1

Ответ:

$\sin( \alpha ) = \sqrt{1 - \cos {}^{2} ( \alpha ) } \\ \sin( \alpha ) = \sqrt{1 - \frac{25}{169} } = \sqrt{ \frac{144}{169} } = \frac{12}{13}$

$5 \sin( 2\alpha ) = 5 \times 2 \sin( \alpha ) \cos( \alpha ) = \\ = 5 \times 2 \times \frac{12}{13} \times \frac{5}{13} = \frac{600}{169}$