Question

Вычислите а) cos300°= b) ctg150°=

Answer 1

A) соs(270 + 30) = sin 30 = 1/2;
b) ctg( 180 -30) = - ctg30 = - √3

Answer 2

A)sin(360-45)=-sqrt(2)/2
b)cos(360-60)=1/2
c)tg(90+30)=-sqrt3
d)ctg(180+60)=1/sqrt3