Question

Помогите пожалуйста срочно любую

Answer 1

$1)Sin(-\frac{45\pi} {6})=-Sin(8 \pi- \frac{\pi} {2})=Sin \frac{\pi} {2}=1\\\\2)Sint=\frac{\sqrt{2}} {2}\\ t=(-1)^{n}arcSin \frac{\sqrt{2}} {2}+ \pi n\\ t=(-1)^{n} \frac{\pi} {4}+ \pi n\\\\ Cost=0\\t=\pi /2 + \pi n$

4) Cos6 > 0

$Sin(- \frac{5\pi} {9})=-Sin( \frac{5\pi} {9})<0\\ Cos6Sin(-\frac{5\pi} {9})<0$