化简 sin(1440°+α).cos(α-1080°﹚∕cos﹙﹣180°-α﹚.sin﹙﹣α-180°﹚
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 12:04:27
![化简 sin(1440°+α).cos(α-1080°﹚∕cos﹙﹣180°-α﹚.sin﹙﹣α-180°﹚](/uploads/image/z/1989314-26-4.jpg?t=%E5%8C%96%E7%AE%80+sin%281440%C2%B0%2B%CE%B1%29.cos%28%CE%B1%EF%BC%8D1080%C2%B0%EF%B9%9A%E2%88%95cos%EF%B9%99%EF%B9%A3180%C2%B0%EF%BC%8D%CE%B1%EF%B9%9A.sin%EF%B9%99%EF%B9%A3%CE%B1%EF%BC%8D180%C2%B0%EF%B9%9A)
化简 sin(1440°+α).cos(α-1080°﹚∕cos﹙﹣180°-α﹚.sin﹙﹣α-180°﹚
化简 sin(1440°+α).cos(α-1080°﹚∕cos﹙﹣180°-α﹚.sin﹙﹣α-180°﹚
化简 sin(1440°+α).cos(α-1080°﹚∕cos﹙﹣180°-α﹚.sin﹙﹣α-180°﹚
sin(1440°+α)=sin(360*4+α)=sinα
cos(α-1080°)=cos(α-360°*3)=cosα
cos(﹣180°-α).=cos(180°+α)=-cosα
sin(﹣α-180°)=-sin(α+180°)=-(-sinα)=sinα
原式=(sinα*cosα)/(-cosα*sinα)=-1