题目内容：

1.sin的三次方(-α)cos(2π+α)tan(-α-π)
2.cos(180°+α)sin(α+360°)/sin(-α-180°)cos(-180°-α)
3.sin(2π-α)cos(π+α)cos(π/2+α)sin(9π/2+α)/cos(π-α)sin(3π-α)sin(-π-α)
4.已知sinα=-3/5,求cosα,tanα的值
5.已知tanα=-根号下3,求sinα、cosα的值