计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/16 04:39:50
计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
![计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)](/uploads/image/z/2389521-57-1.jpg?t=%E8%AE%A1%E7%AE%97cos%28a%2B5%CF%80%2F12%29cos%28a%2B%CF%80%2F6%29%2Bcos%28%CF%80%2F12-a%29cos%28%CF%80%2F3-a%EF%BC%89)
cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
=sin(π/2-(a+5π/12))cos(a+π/6)+cos(π/12-a)sin(π/2-(π/3-a))
=sin(π/12-a)cos(a+π/6)+cos(π/12-a)sin(a+π/6)
=sin(π/12-a+a+π/6)
=sin(π/12+π/6)
=sinπ/4
=√2/2
=sin(π/2-(a+5π/12))cos(a+π/6)+cos(π/12-a)sin(π/2-(π/3-a))
=sin(π/12-a)cos(a+π/6)+cos(π/12-a)sin(a+π/6)
=sin(π/12-a+a+π/6)
=sin(π/12+π/6)
=sinπ/4
=√2/2
计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
cos^2(π/3-a)+cos^2(π/6+a)
已知cos(π/6-a)=根号3/3,求cos(5π/6+a)-cos²(π/3+a)
已知cos(a+π6
化简sin(2π+a)cos(π-a)cos(π/2-a)cos(7π/2-a)/cos(π-a)sin(3π-a)si
如果cos(π+A)=−12
【1】化简:sin(a-5π)/cos(3π-a)×cos(π/2-a)/sin(a-3π)×cos(8π-a)/sin
cos(5π-a)+sin(2π-a)分之cos(-a)-sin(3π-a)=()要答案和计算过程,过程要详细
已知cos(a-b)=-12/13 cos(a+b)=12/13且π/2
已知a为第三象限角,且f(a)=sin(5π-a)cos(a+3π/2)cos(π+a)/sin(a-3π/2)cos(
已知cos-4/5,且a为第三象限角,求cos(a+3/π)
cos(6π-a)等于多少啊?