Ответ: sin(6π+t) = 21/29 ⇒ sint = 21/290 < t < π/2 ⇒ 0 < cost < 1cost = КОРЕНЬ (1−sin²t) = КОРЕНЬ (1−441/841) == КОРЕНЬ (400/841) = 20/29tg(π+t) = tgt = sint/cost = 21⋅29/(29⋅20) = 21/20 = 1+1/20 = 1,05