求y=2sin(x/2)+3cos(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)=? 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) 求y=sin x/(2-cos x)值域 已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 2sin^2x - 5sin x cos x=3 cos^2x,求X, 已知Sin x+Sin y=1/2,Cos x+Cos y=根号3/3,求S求Sin(x-y)/2 y=(sin x + COS x)^2 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) y=2cos x (sin x+cos x) sin^2x+cos^2y=1/2 求3sin^2x+sin^2y的最值 已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x 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