求y=sin x/2 + cos x/3 的最小正周期.

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) sin(x+y)sin(x-y)=k,求cos^2x-cos^2y 当cos^2x-cos^2y=√3/2时,求sin(x+y）×sin(x-y) 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)+3cos(x)=2,求sin(x)-cos(x)/sin(x)+cos(x)=? 已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 已知Sin x+Sin y=1/2,Cos x+Cos y=根号3/3,求S求Sin(x-y)/2 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) 求y=sin x/(2-cos x)值域 2sin^2x - 5sin x cos x=3 cos^2x,求X, 问道三角函数题已知sin(x)-sin(y)=-(2/3);cos(x)-cos(y)=(2/3);求cos(x-y) sin^2x+cos^2y=1/2 求3sin^2x+sin^2y的最值 y=(sin x + COS x)^2 y=2cos x (sin x+cos x) 求y=cos(-x^3)+（sin^2)(x^3)+ln(-x)^3的导函数. 求下列函数的导数:y=x-sin x/2 cos x/2 y=x^3+3^x