
  c = [73 -36 0 0 0]
  A = toeplitz(c,c)
  f = [1; 2; 3; 4; 5]
  u = A \ f
  x = 1/6 : 1/6 : 5/6;
  
  C = [1 1; exp(1) exp(-1)]
  d = [0 ; -6]
  b = C \ d
  x2 = 1/6 : 1/60 : 5/6;
  y = b(1,1)*exp(x2) + b(2,1)*exp(-x2) + 6*x2;

  plot(x,u,x2,y)
  legend('approximate','exact')
   
   
