Решите тригонометрические уравнения: 1. 2sin 2 x – 5sin x – 7 = 0 2. 12sin 2 x + 20cos x – 19 = 0 3. 3sin 2 x + 14sin x cos x + 8cos 2 x = 0 4. 7 tg x – 10ctg x + 9 = 0 5 . 5sin 2 x – 14cos 2 x + 2 = 0 6 . 9cos 2 x – 4cos 2 x = 11sin 2 x + 9