如果y=tan(x),如何证明y'''=2(1+y^2)(1+3y^2)
y′=y/x+tan[(y/x)^2]
设y=(tan^2 x-csc^2 x )/(tan^2 x+cot^2 x -1) (a)证明y=1- 2/(tan^
已知sin(x+y)=1,求证:tan(2x+3y)=tany
如何求函数 定义域 例如:(1)y=1/1-tanx (2)y=1/1+2sinx (3) y=-tan(x+π/6)+
(1)y=根号-sinx定义域,(2)y=tan(x+派/3)
sin(x+y)=1\2,sin(x—y)=1\3,求[tan(x+y)-tanx-tany]\[tany的平方tan(
1.y=x arctanx - 1/2 ln(1+x^2) 求dy 2.y=tan(3x^2+1) 求y的导数即y' 3
请问怎么证明sinX+sin(X+Y)+sin(X+2Y)/cosX+cos(X+Y)+cos(X+2Y)=tan(X+
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
用柯西不等式证明:如果x,y,z为正数,x+y+z=1,则x^2+y^2+z^2>=1/3