cos^4(x)-sin^4(x)+2sin^x的值等于

化简[1-(sin^4x-sin^2cos^2x+cos^4x)/(sin^2)]+3sin^2x 已知cos 2x=3/5,求sin^4 x+cos^4 x的值 sin（sin（sin（sin（x）=cos（cos（cos（cos（x）,X等于多少? 已知sin X+cos X=m,|m|小于等于根号2且|m|不等于1,求sin X^3+cos X^3,sin X^4+ cos^4(x)-sin^4(x)等于?是cos^2(x)还是cos2x (1-(sin^4x-sin^2xcos^2x+cos^4x)/sin^2x +3sin^2x 证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4 用cos x表示sin^4 x -sin^2 x +cos^2 x 证明sin x+cos x的最大值等于 根号2 sin^2x+cos^2x)(sin^4x-sin^2xcos^2x+cos^4x) =sin^4x-sin^2xcos 请问cos^2x/sin^4x的不定积分是多少 sin（π/4-x)为什么等于cos(x+π/4)