计算tan(－1560度)cos(17π/6)

网友回答

tan(-1560º)cos(17π/6)=tan(-1800º+240º)cos(17π/6-2π)=tan(240º)cos(5π/6)=tan(180º+60º)×cos(5π/6)=tan60ºcos(5π/6)=(√3)×(-√3/2)=-1.5
======以下答案可供参考======
供参考答案1:
tan(－1560°)×cos(17π/6)
=tan(－9×180°＋60°)×cos(3π＋π/6)
=(tan60°)×(－cos30°)
=(√3)×(－√3/2)
=－3/2供参考答案2:
负的二分之三，打错了
供参考答案3:
tan（-1560度）cos（6分之17派）
=tan（1440-1560度）cos（6分之17派-2π）=tan(-120)cos(5π/6)=-√3*(-√3/2)=3/2
供参考答案4:
tan(－1560°)cos(17π/6)
=tan(－360°×5+240°)cos(2π+(5π/6))
=tan240°cos(5π/6)
=tan(240°π/180°)cos(5π/6)
=tan(4π/3)cos(5π/6)
=tan(π+(π/3))×cos(π-(π/6))
=tan(π/3)×(-cos(π/6))
=√3×(-√3/2)
=-3/2