化简y=sin^4x-cos^4x,

化简y=sin^4x-cos^4x, y=sin^4x+cos^4x的值域 化简sin (x+y)sin x +cos (x+y)cos x= 函数y=cos^4x-sin^4x的最小正周期y=(cos^2x+sin^2x)(cos^2x-sin^2x)为什么等于cos^2x-sin^2x=cos2x谢谢 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) 函数y=sin(x)cos(x+ π/4)+cos(x)sin(x+π/4)的最小正周期是 y=4√2sin x cos x+cos 2x 的值域是 6-4x-x^2=5/|sin(y/x)cos(y/x)|的解 求函数y=7-4sin(x)cos(x)+4cos^2(x)-4cos^4(x)值 y=sin²x*cos^4 的最大值 化简sin^4x-sin^2x+cos^2x 化简:sin^4 x-sin^2 x+cos^2 x 化简cos^4x+sin^4x 化简:cos^4(X)-sin^4(X) 化简sin^4x+cos^2x 化简(sin^2x-cos^4x+cos^2x-sin^4x)/(sin^2x-cos^6x+cos^2x-sin^6x) 化简：y=cos^4 x＋2 sinxcosx－sin^4 x y=sin^4x+2√3 sinxcosx-cos^4x 化简