Perform these essential matrix functions on matrix M:

   M =  5.2  -4.1
       -4.1   5.2
   e = eigenvalues of M
   v = eigenvectors of M
 

M = [[5.2;-4.1];[-4.1;5.2]]
e = eigen(M)[1:2,3]
v = eigen(M)[1:2,1:2]

  Add and plot vectors
  Plot functions