求证：4(cos^6 x +sin^6 x) = 1 + 3cos^2 2x4(cos^6 x +sin^6 x) = 1 + 3cos^2 2x谢谢～～～

求证：1-cos^4x-sin^4x/1-cos^6x-sin^6x=2/3 三角等式求证：cos^6x+sin^6x=1-3sin^2x+3sin^4x 求证(2-2cos^6x-2sin^6x)/(3-3cos^4x-3sin^4x)-(1/4)sin^2(2x)-cos^4x=sin^2x 化简(sin^2x-cos^4x+cos^2x-sin^4x)/(sin^2x-cos^6x+cos^2x-sin^6x) 求证：4(cos^6 x +sin^6 x) = 1 + 3cos^2 2x4(cos^6 x +sin^6 x) = 1 + 3cos^2 2x谢谢～～～ 求证sin^4x-cos^4x=sin^2x-cos^2x 化简 1-sin^4x-cos^4x/1-sin^6x-cos^6x 化简(1-cos^4x-sin^4x)/(1-cos^6x-sin^6x) 求值：(1-sin^6 x-cos^6 x)/(1-sin^4 x-cos^4 x) 2(sin^6x+cos^6)-3(sin^4x+cos^4x) 求证（cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2x 求证 tan（2π-X）sin（-2π-X）cos（6π-X）/ sin（X+3π/2)*cos（X+3π/2)=-tanX 证明一个sin&cos的等式证明 1+sin^2(x)+sin^4(x)+sin^6(x)=[1-sin^8(x)]/[cos^2(x)] 求证(3-sin^4 x-cos^4 x)/2cos^2 x=1+tan^2 x+sin^2 x 求证sin^4x+cos^4x=1-2sin^2xcos^2x 求证 sinˇ4X+sin²Xcos²X+cos²X = 1 求证（cos^2x-sin^2x)(cos^4x+sin^4x）+1/4sin2xsin4x=cos2x 关于sin^2x+cos^2x 的应用式子：cos^6x+sin^6x=（cos^2x+sin^2x)(cos^4x-cos^2xsin^x+sin^4x)=(cos^2x+sin^2x)^2-3sin^2xcos^2x 求这两步算法中的具体思路 ps:cos^2x=cosx的二次方