Proving a property with logarithm

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For a polynomial $V(x)$ of degree $r$ defined in $\mathbb{R}^d$, we denote

$$A_V(x)=\sum_{1\le |\alpha|\le r}|\partial^{\alpha}_xV(x)|^{\frac{1}{|\alpha|}}$$

I want to prove the following result: there exists a constant $c>0$ such that for all $x,x_0\in \mathbb{R}^d$
$$ |x-x_0|\le \Bigl(\frac{A_V(x)}{ \log(A_V(x))}\Bigr)^{-1}$$ implies $$ \left(\frac{\dfrac{A_V(x)}{\log(A_V(x))}}{\dfrac{A_V(x_0)}{ \log(A_V(x_0))}}\right)^{\pm 1}\le c. $$

Here we consider polynomials $V$ such that $A_V(x)\neq 1$ for all $x\in \mathbb{R}^d$.

Please help me to do so.

Thanks in advance