Question

помогите пожалуйста((

Answer 1

Ответ:

б

$\frac{1 - \cos {}^{2} ( \alpha ) }{ \sin {}^{2} ( \alpha ) } = \frac{ \sin {}^{2} ( \alpha ) }{ \sin {}^{2} ( \alpha ) } = 1$

в

$\sin {}^{2} ( \alpha ) + (1 - \cos {}^{2} ( \alpha ) ) = \sin {}^{2} ( \alpha ) + \sin {}^{2} ( \alpha ) = 2 \sin {}^{2} ( \alpha )$

г

$\frac{1 - \sin {}^{2} ( \alpha ) }{1 - \cos {}^{2} ( \alpha ) } = \frac{ \cos {}^{2} ( \alpha ) }{ \sin {}^{2} ( \alpha ) } = ctg {}^{2} \alpha$

д

$\sin( \alpha ) ctg \alpha = \sin( \alpha ) \times \frac{ \cos( \alpha ) }{ \sin( \alpha ) } = \cos( \alpha )$