Lemma 3.3 Suppose $u \in H^{1}(\Omega)$ satisfies $\int_{B_r(x_0)}|Du|^2 \le M r^{^\mu} \quad \mbox{for any} \ \ B_r(x_0) \subset \Omega,$ for some $\mu \in [0,n)$. Then, for any $\Omega' \Subset \Omega$ there holds for any $B_r(x_0) \subset \Omega$ with $x_0 \in \Omega'$ $\int_{B_r(x_0)} |u|^2 \le C(n,\lambda,\mu,\Omega,\Omega')\, \left \{M+\int_{\Omega}u^2\right \} r^{\lambda}$ where $\lambda = \mu +2$ if $\mu < n-2$ and $\lambda$ is any number in $[0,n)$ if $n-2\le\mu
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Proof. Denote $R_0= \mbox{dist}(x,\partial \Omega)$. For any $x_0 \in \Omega'$ and $0
Then, following the proof, I understand the case $\lambda = \mu +2$ if $\mu < n-2$. But I don't understand how to obtain the case $\lambda$ is any number in $[0,n)$ if $n-2\le\mu