How do i show the following bilinear operator is continuous and coercieve ?

Question

We have $Lu=-\sum_{i,j=1}^n (a^{ij}u_{x_i})_{x_j}+cu$ , I want to show that there exists a constant $\mu \ge0$ such that Bilinear $B$ satisfies Lax milgram hypothesis for every $c(x) \ge 0$. I am basically not able to show that it is continuous and it is coercieve . How can i do it ? A binilinear form is continuous if $|B[u,v]\le\alpha||u|| ||v|||$ and coercive if $B[u,u]\ge\beta||u||^2$ , where $\beta, \alpha>0 $ This is a problem from Evans chapter 6. Thanks a lot .