17 задание срочно!!!50 балов даю

1) $2sin(120^{o} ) + 4cos(150^{o}) - 2 tg(135^{o}) = 2sin(60^{o} ) - 4cos(30^{o}) + 2 tg(45^{o}) = \sqrt{3} - 2\sqrt{3} + 2 = 2 - \sqrt{3}$

2) $cos(120^{o} ) - 8sin^{2}(150^{o}) + 3 cos(90^{o})cos(162^{o}) = - cos(60^{o} ) - 8sin^{2}(30^{o}) + 3 * 0 * cos(162^{o}) = -\frac{1}{2} - 2 + 0 = -2,5$

3) $cos(180^{o})(sin(135^{o})tg(60^{o}) - cos(135^{o}))^{2} = -1 * (sin(45^{o})tg(60^{o}) + cos(45^{o}))^{2} = -1 * (\frac{\sqrt{2}}{2} * \sqrt{3} + \frac{\sqrt{2}}{2})^{2} = -\frac{1}{2} * (\sqrt{3} + 1)^{2} = -\frac{1}{2} * (3 + 2\sqrt{3} + 1) = -2-\sqrt{3}$