诱导公式求cos17⼀3π,具体过程

2025-03-24 00:28:36
推荐回答(2个)
回答1:


如图

回答2:

cos17/3兀=cos3/5兀
=cos(兀十2/3兀)
=一cos2/3兀
=一cos(兀一1/3兀)
= cos1/3兀
=二分之根号三