求y=log(cos^2-sin^2x)的定义域并求单调增区间

求y=log(cos^2-sin^2x)的定义域并求单调增区间 sin(x+y)sin(x-y)=k,求cos^2x-cos^2y y =(cos^2) x - sin (3^x),求y' Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y) matlab求导数好像每次都不行,每次都说代码不完整或错误>> a=diff([sqrt(x^2- 2*x+5),cos(x^2)+2*cos(2*x),4^(sin(x)),log(log(x))]).a=diff([sqrt(x^2- 2*x+5),cos(x^2)+2*cos(2*x),4^(sin(x)),log(log(x))]).|Error:Expression or statement is 求y=sin x/(2-cos x)值域 当cos^2x-cos^2y=√3/2时,求sin(x+y）×sin(x-y) y=(sin x + COS x)^2 y=2cos x (sin x+cos x) 求y=（1+cos x)/(sin x+cos x+2)的值域. 已知函数y=(sin x+ cos x)(sin x+cos x)+2cos x*cos x ,求它的递减区间语气亲和、态度友好 化简y=sin^2 x + cos 2x 求周期sin^2 x 是平方 y=1-sin(2x)/sin(x)-cos(x)求T.最值 2sin^2x+cos^2y=1,求sin^2x+cos^2y的取值范围 求函数y =cos 2x +sin 2x /cos 2x -sin 2x 的最小正周期 求y=sin＾2(x)+3sin(x)cos(x)-2cos＾2(x)的最大值 求y=sin x +2sin x cos x -3cos²x 的周期和值域, 已知Sin x+Sin y=1/2,Cos x+Cos y=根号3/3,求S求Sin(x-y)/2