当y=0时,
1+0+x²-1=0
x=0.
隐函数求导法则：
两边对x求导
(e^y)y'+6y+6xy'+2x=0[***]
令y=0,x=0求y'(0):
y'+0+0+0=0,y'(0)=0.
对[***]两边再求导
(e^y)(y')^2+(e^y)y''+6y'+6y'+6xy''+2=0
代入x=0,y=0,y'=0
y''+2=0
y''(0)=-2