sin(5/4*π)*cos(4/5*π)*tan(11/6*π)判断符号,
sin(5/4*π)*cos(4/5*π)*tan(11/6*π)判断符号,
判断下列三角函数符号sin(-17/5派),cos(-23/4π),cos940°,cos-59/17π
确定3角涵数值符号Sin 4 Cos 5 tan 8 tan(-3)
已知sin a=2cos a 计算⑴(sinα+2cosα)/(5cosα-sinα) ⑵tan(α+π/4)
tan(a-4π)cos(π+a)sin^2(a+3π)/tan(3π+a)cos^2(2/5π+2)=0.5,求tan
已知6sin²α+5sinαcosα-4cos²α=0,α∈(3π/2,2π),求tanα的值
cosπ/3+tanπ/4+3tan²π/6+sinπ/2+cosπ+sin3π/2等于?.
化简sin(3π-x)cos(x-3/2)cos(4π-x)/tan(x-5π)cos(π/2+x)sin(x-5/2π
已知cosα=-4/5,α∈(π,2π),求sinα,tanα
化简sin(θ-5π)•cot(π2-θ)•cos(8π-θ)tan(3π-θ)•tan(θ-32π)•sin(-θ-4
求证tan(2π-α)sin(-2π-α)cos(6π-α)/cos(α-π)sin(5π-α)=-tanα
求证(tan(2π-θ)sin(2π-θ)cos(6π-θ))/((-cosθ)sin(5π+θ))=tanθ