利用公式求cos(-6分之79派)的三角函数值

2025-02-26 07:37:55
推荐回答(1个)
回答1:

cos(-π-1/6π)
=-cos(π/6)
=-(根号3)/2

cos(-7π/6+2π)
=cos(5π/6)
=cos(π-π/6)
=-cos(π/6)
=-(根号3/2)