化简cos²(α-π/4)-sin²(π/4-α)~
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/02 11:02:06
![化简cos²(α-π/4)-sin²(π/4-α)~](/uploads/image/z/637703-71-3.jpg?t=%E5%8C%96%E7%AE%80cos%26%23178%3B%EF%BC%88%CE%B1-%CF%80%2F4%EF%BC%89-sin%26%23178%3B%EF%BC%88%CF%80%2F4-%CE%B1%EF%BC%89%7E)
x){3b5eCs{:m=ߠo~Onqf\${n#P&H<v6|{fp``m`uBE
5"FH" 0VD<;gl T7As1\ǧS0e6"9
M
化简cos²(α-π/4)-sin²(π/4-α)~
化简cos²(α-π/4)-sin²(π/4-α)~
化简cos²(α-π/4)-sin²(π/4-α)~
答:
cos²(a-π/4)-sin²(π/4-a)
=cos²(a-π/4)-sin²(a-π/4)
=cos(2a-π/2)
=cos(π/2-2a)
=sin2a
cos²(α-π/4)-sin²(π/4-α)
=cos²(π/4-α)-sin²(π/4-α)
=cos2(π/4-α)
=cos(π/2-2α)
=sin2α