化简：cos^4x+sin^2xcos^2x+cos^2x

sin^8X+cos^8X+4sin^2Xcos^2x-2sin^4xcos^4X(化简） 化简：cos^4x+sin^2xcos^2x+cos^2x 化简sin^4x+sin^2xcos^2x+cos^2x=?(请写过程) 化简cos^4x+sin^2xcos^2x+sin^2x 化简[1-(sin^4 x-sin^2 xcos^2 x+cos^4 x)]/(sin^2 x)+3sin^2 x 化简(sin^4+cos^4+sin^2xcos^2x)/(2-sin2x) 化简：cos^2x(2cos^2x+3)-sin^2x(2cos^2x+3)-4sin^2xcos^2x+3 求证sin^4x+cos^4x=1-2sin^2xcos^2x sin^4x+cos^4x=1-2sin^2Xcos^2X谢谢额 (1-(sin^4x-sin^2xcos^2x+cos^4x)/sin^2x +3sin^2x sin^4+sin^2xcos^2x+cos^2x 证明 =1 cos xsin b-sin xcos b和sin xcos x- sin^2x+cos^2x)(sin^4x-sin^2xcos^2x+cos^4x) =sin^4x-sin^2xcos^2x+cos^4x 是根据什么化简的? 1-2sin xcos x/cos的平方x 化简sin^2x+sin^2y-sin^2xsin^2y+cos^2xcos^2y sin^4x-sin^2xcos^2x+cos^4x =(sin^2x+cos^2x)^2-3sin^2xcos^2x 那么这个依据呢?老师 y=7-4sin xcos x+4cos^2 x-4cos^4 x的最大值和最小值? 求sin^4x+cos^4x+4sin^2xcos^2x-1的最小正周期及值域.