Question

алгебра тригонометрия 2 задания
100​

Answer 1

Ответ:

5

$\frac{ \sin( \frac{3\pi}{2} - x ) \cos {}^{2} (\pi + x)tg(x - \frac{\pi}{2} ) }{tg(\pi - x) \times \cos(x - \pi) \sin(2.5\pi + x) } = \\ = \frac{ - \cos(x) \times \cos {}^{2} ( x ) \times( - ctg(x))}{ - tgx \times ( - \cos(x)) \times \cos(x) } = \\ = ctgx \times ctgx = ctg {}^{2} x$

6

$(1 - \cos {}^{2} (x)) (1 + {ctg}^{2}x) = \sin {}^{2} (x) \times (1 + \frac{ \cos {}^{2} (x) }{ \sin {}^{2} (x) } ) = \\ = \sin {}^{2} (x) \times \frac{ \sin {}^{2} (x) + \cos {}^{2} (x) }{ \sin {}^{2} (x) } = 1$