什么叫规则角?角度还有规则这一说么?
告诉你几个好记的吧：
sin30 = 1/2 cos30 = √3/2
sin60 = √3/2 sin60 = 1/2
sin45 = cos45 = √2/2
sin90 = 1 cos90 = 0
sin0 = 0 cos0 = 1
什么叫规则角?角度还有规则这一说么?
告诉你几个好记的吧：
sin30 = 1/2 cos30 = √3/2
sin60 = √3/2 sin60 = 1/2
sin45 = cos45 = √2/2
sin90 = 1 cos90 = 0
sin0 = 0 cos0 = 1