怎样化简函数 cosπ/4cosπ/3-sinπ/4sinπ/3cosπ/4cosπ/3-sinπ/4sinπ/3

怎样化简函数 cosπ/4cosπ/3-sinπ/4sinπ/3cosπ/4cosπ/3-sinπ/4sinπ/3 cos(2x-1/3π)+cos(2x+6/π)怎样化成一角一函数 cosθ^2+cos(θ+π/3)^2-cosθcos(θ+π/3)化简如何化简 化简求值cos(π/7)cos(2π/7)cos(4π/7) COS(π/7)+COS(3π/7)+COS(5π/7)化简求值, 计算：cos（π/5)+cos（2π/5)+cos(3π/5)+cos(4π/5) 函数 (4 20:28:50)cos^4 (π /8)+cos^4(3π/8)+cos^4(5π/8)+cos^4(7π/8) = 函数fx=cos（2x-π/3）+cos（2x+π/6）这个式子怎么化简 化简函数y=cos^2(x+7π/12)-cos^2(x+π/12), 求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11) 求值：cos(π/11)-cos(2π/11)+cos(3π/11)-cos(4π/11)+cos(5π/11) cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11) cosπ/3－tanπ/4+cosπ－sin3π/2 化简计算 证明:函数f(x)=cos^2+cos^2(x+π/3)+cos^2(x-π/3)是常数函数 函数y=cos(2x-π/4)怎样化成sin形式 Cos(α-π) Cos(α- π/2 )如何化简 求数学高手帮忙cos(2π/7)+cos(4π/7))+cos(6π/7)=?(化简求值) cos(x)*cos(π/6-x) 接下来怎么化简