Consider a system of multivariate polynomial equations
$\vec{x}= f(\vec{x})$ with integer coefficients, $f$ is at most of degree 2.
Suppose $\vec{x}_1$ and $\vec{x}_2$ are two real roots of $f$, is there any bound on
$||\vec{x}_1-\vec{x}_2||$ (in terms of $\infty$-norm or $1$-norm)?