Please i need help for this for $w\in W^{1,p}(\mathbb{R}^N)$, we define $w_R(x)=h_{R}(x)w(x)$
where $h\in C_0^{\infty}(\mathbb{R}^N,[0,1]), h(x)=1,~ x\in B_1(0)$ and $h(x)=0,~ x\in B^c_2(0)$ and $R>0$ , $h_{R}(x)=h(\frac{x}{R})$
How to show that
$$\lim_{n\to\infty}\int_{\mathbb{R}^N}(|\nabla w_{R_n}|^p+|w_{R_n}|^p)dx=\int_{\mathbb{R}^N}(|\nabla w|^p+|w|^p)dx$$
with $(R_n)$ is a real sequence such that $R_{n}\to \infty$ when $n\to\infty$.