Question

А) 2sin45*cos45 B) cos^2 240-sin^2 240 C) 2tg75/1-tg^2 75

Answer 1

1) 2sin90= 2*1=2
2) соs 480 = cos (360+120)= cos 120 = - 0.5
3) tg 150 = tg (180-30)= - tg 30= - √3/3= - 1/ √3