请问:1.sin(x)=1/3,sec(y)= 25/24,x和y 在0到π/2中间,求cos(x+y).
Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y)
y =(cos^2) x - sin (3^x),求y'
1.y=cos^4x+sin^4x 求周期 2.y=(sin2x+sin(2x+π/3))/( cos2x+cos(2x
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
sin(x+y)sin(x-y)=k,求cos^2x-cos^2y
参数方程化普通方程 1.x=2secθ y=2tanθ (0≤<2π)2.x=cos^2θ y=2-sin^2θ 3.x
cos(x+y)=?sin(x+y)=?
如果y=|sin x+cos x+tan x+cot x+sec x+cscx| 那么y的最小值是多少?
求y=sin(x-派/3)cos x的周期及最大值和最小值
求函数y=sin^2(x+π/6)+cos^2(x+π/3)的最大值和最小值?
sin^2x+cos^2y=1/2 求3sin^2x+sin^2y的最值
求下列函数的导数(1)y=4sin(3x-1) (2)y=cos^2·3x (3)y=(x^2