Найти значение
Sin a , tg a , cos a , если ctg a = 8/15 , п<a<3п/2

tga = 1/ctga = 15/8tga = sina/cosa = 15/8 = 1,875sina = 1,875cosacosa = -√(1-sin²a)sina = -15/8√(1-sin²a)sin²a = 225/64(1-sin²a)289/64sin²a = 225/64sin²a = 225/289sina = -15/17cosa = -√(1-225/289)=-8/17Ответ: -15/17; 15/8; -8;17