化简cos2x/[2cot(π/4+x)cos平方(π/4-x)]

化简cos2x/[2cot(π/4+x)cos平方(π/4-x)] 化简(1+cos2x)/{cot(x/2）-tan（x/2)} 求证:cos^8x-sin^8x-cos2x = 1/8(cos6x - cos2x)还有，csc^4a(1-cos^4a)-2cot^2a 已知4sin^2x-cos^2x+3cosx=0求(cos2x-cos^2x)/(1-cot^2x) 求下列不定积分：1、(cot)^2•xdx 2、cos2x/(cos^2xsin^2x)dx cot(π/2-X)等于什么? 2sin(x-π/4)sin(x+π/4)=?答案是-cos2x 还是cos2x 化简f(x)=cos(2x-π/3)-cos2x 化简tan（π-x）×cot（x-π）+cos²y-2cos²x 已知4sin²x-cos²x-6sinx+3cosx=0,求（cos2x-cos²x）/1-cot²x的值 化简：cos^2x / ( cot(x/2)-tan(x/2) ) 化简：cos^2x / ( cot(x/2)-tan(x/2) ) y=e^(sinx)+2^(根号x) y=(2x+1)^5(4-x)^3 y=2x^2*tan(根y=e^(sinx)+2^(根号x)y=(2x+1)^5(4-x)^3y=2x^2*tan(根号x)y=cos2x/(1+x)y=e^(πx)sinπxy=e^(x^2)cot(1/x)今天才教 化简cos2x/sin（x+π/4）急! 化简2cos2x(sinx-cos2x) y=2cos2x+sin平方x-4cosx.化简 为什么sin2x+cos2x=2sin(2x+π/4) cot^2x+1 是多少cot平方x +1