[Please use Matlab to solve this question! Please give the code! Or at least give me the way to construct 'An' in Matlab, thx!]

1. Consider the linear system Anp- p, where An is an n x n matrix with 2's on the main diagonal, -1's directly above and below the main diagonal and 0's everywhere else. For instance, As is -1000 1 21 0 0 As-0 -1 2 -1 0 0 0-1 2-1 0 0 02 This is a discretized version of Poisson's equation: -?=p. This equation appears very often in physical applications. We will discuss dis- cretizations and differential equations, including the origin of this matrix An, later in the class. Construct the matrix A80 in Matlab. In addition, make the 80 1 vector ? such that the jth entry of ? is defined according to the formula 50x/81 sin81 50Tj