设y=f(x)
则g''(y)=d(dx/dy)/dy
=d(dx/dy)/dx * dx/dy
=d(1/(dy/dx))/dx * 1/(dy/dx)
=-f''(x)/[f'(x)]^2 * 1/f'(x)
=-f''(x)/[f'(x)]^3
所以g''(2)=3√3
设y=f(x)
则g''(y)=d(dx/dy)/dy
=d(dx/dy)/dx * dx/dy
=d(1/(dy/dx))/dx * 1/(dy/dx)
=-f''(x)/[f'(x)]^2 * 1/f'(x)
=-f''(x)/[f'(x)]^3
所以g''(2)=3√3