Can anyone help me to solve below exercise?
Let $R$ be a Noetherian ring and $M$ a finitely generated $R$-module. Let $\underline{a}=\{a_1,\cdots,a_n\}$ be a maximal $M$-regular sequence and $I\subseteq Q\in\operatorname{Ass}_{R}(\dfrac{M}{\langle\underline{a}\rangle M})$. If $P\in\operatorname{Spec}(R)$ such that $Q\subseteq P$, show that
$$\operatorname{depth}_I(M)=\operatorname{depth}_{I_P}(M_P) $$
Thanks for any help or idea.