Question

Помогите решить, пожалуйста
sin315°×cos225°=
sin330°×cos300°=
sin729°=
sin526°=
cos531°=
cos548°=
cos579°=

Answer 1

sin315°×cos225°=$- \frac{ \sqrt{2} }{2} \times ( - \frac{ \sqrt{2} }{2} ) =\frac{2}{4} = \frac{1}{2}$
sin330°×cos300°=
$- \frac{1}{2} \times \frac{1}{2} = - \frac{1}{4}$
sin729°=sin9°=0.156
sin526°=sin166°=0.241
cos531°=cos171°=0.987
cos548°=cos188°=-0.99
cos579°=cos219°=-0.777