Question

найти sina cos2a tga если cosa=0.6 и 0

Answer 1

при cos(a)=0.6
sin(a) = sqrt (1 - cos ^ 2 (a)) = sqrt(1 - 0.36) = 0.8
cos 2a = cos ^ 2 (a) - sin ^ 2 (a) = -0.28
tg (a) = sin (a) / cos (a) = 0.8 / 0.6 = 4/3

при cos(a)=0
sin (a) = 1
cos 2a = -1
tg (a) - не существует