Ответ:
Пошаговое объяснение:
2) (5sin2x) : 4sin4x = (5sin2x) :(8sin2xcos2x) = 0,625/cos2x = 5/8cos2x; 3) cosx = 1/√5 ⇒ sinx = - √1-cos²x = - √1 -1/5 = - √4/5 = - 2/√5 ⇒ - √45 · sin2x = - √45 ·2 sinx cosx = -√45 ·2 ·( - 2/√5) · 1/√5 = 12/√5 5) tg3x = 1 ⇒ 3x = π/4 + πn, n ∈ Z, x = π/12 + π/3 n, n ∈ Z b) π/12; 5π/12; 3π/12; 13π/12; 17π/12; так как x ∈ (0; 3π/2)