Question 2Among all the nonzero real numbers $x,y,z$ satisfying $x+y+z=0$, find the largest possible value of $$\frac{y+z}{yz}(y^2+z^2-x^2)+\frac{z+x}{zx}(z^2+x^2-y^2)+\frac{x+y}{xy}(x^2+y^2-z^2).$$