Question

Вычислить:
1) cos (-45)
2) sin (-60)
3) ctg(-30)
4) tg (-45)
5) sin (-п/6)
6) ctg (-п/3)

Answer 1

$1)Cos(-45^{o})= Cos45^{0} =frac{sqrt{2} }{2}\\2)Sin(-60^{o})=-Sin60^{o} =-frac{sqrt{3} }{2}\\3)Ctg(-30^{o})=-Ctg30^{o}=-sqrt{3}\\4)tg(-45^{o})=-tg45^{o} =-1\\5)Sin(-frac{pi }{6})=-Sinfrac{pi }{6} =-frac{1}{2}\\6)Ctg(-frac{pi }{3})=-Ctgfrac{pi }{3}=-frac{sqrt{3} }{3}$