Question

5sin(-п/3)+2cos(-п/3)/cos(-п/2)+sin3п/2

Answer 1

$5\, sin(-\frac{\pi}{3})+2\, cos(-\frac{\pi}{3})\cdot cos(-\frac{\pi}{2})+sin\frac{3\pi }{2}=\\\\=-5\cdot sin\frac{\pi }{3}+2\, cos\frac{\pi }{3}\cdot cos\frac{\pi }{2}+(-1)=\\\\=-5\cdot \frac{\sqrt3}{2}+2\cdot \frac{1}{2}\cdot 0-1=-\frac{5\sqrt3}{2}-1=-\frac{5\sqrt3+2}{2}$