cos(x+π/6)=1/3,(0

cos(x+π/6)=1/3,(0 证明cos 2x cos x=1/2(cos x+cos 3x) 已知cos(x-π/6)=-根号三分之三 则cos(x)+cos(x-π/3)的值是 y=cos(π/3-x)cos[π/2（x-1)]判断奇偶性y=cos(π/3-x)cos(π/3+x)判断奇偶性 急,matlab解非线性方程组用什么函数呢 方程如下所示：(cos(x(1))*cos(x(3))-sin(x(1))*cos(x(2))*sin(x(3)))*(194-x(4))*x(7)+(cos(x(1))*sin(x(3))+sin(x(1))*cos(x(2))*cos(x(3)))*(145-x(5))*x(7)+sin(x(1))*sin(x(2))*x(6)*x(7)-1=0;(-sin(x(1 已知sin[a-b]cos a-cos[b-a]sin a=3/5,b是第三象限角,求sin[b+5π/4]的值第一题1/2cos x-√3/2sin x第二题√3sin x+cos x第三题√2[sin x-cos x]第四题√2cos x-√6sin x 【高一数学】已知函数fx=2cos^2x+cos(2x+π/3)已知函数fx=2cos²x+cos(2x+π/3）(1)f(α)=√3/3+1,0 为什么cos(2x-π/3)-sin(5π/6) =cos(2x-π/3)? cos(x-π/6)=m,则cosx+cos(x-π/3)=_______ cos(2x-π)/[根号2cos(x+π/4)]=-1/5,0 cos(2x-1/3π)+cos(2x+6/π)怎样化成一角一函数 已知4sin^2 x – 6sinx – cos^2 x + 3cosx = 0 ,求 cos(2x +π/4) / [(1-cos2x)(已知4sin^2 x – 6sinx =cos^2 x -3cosx ,求 cos(2x +π/4) / (1-cos2x)(1-tan2x)的值 【高中数学】已知cos(x+y)=1/3,cos(x-y)=2/3,且0 已知cos(x+y)=1/3,cos(x-y)+2/3,且0 (x)=sin(ωx-π/6)-2cos²(ω/2)x+1 =(√3/2)sinωx-(1/2)cosωx-cosωx怎么得的-coswx cos(π/6-x)=sin(π/3+x)?为什么 函数f(x){lg(x+1),x>0 cosπx/2,x函数f(x)={lg(x+1),x>0 cosπx/2,x cos(x+π/6)=-1/2,怎么求x、?