1 We consider the system of linear equations Hx = b given by the following symmetric (strictly) row-wise diagonally dominant and (strictly) positive definite matrix 4 1 4 1 H E Rnxn 1 0 0 1 4 0 1 0 0 1 0 0 4 1 0 4 1 1 4 of dimension n = 100 and right-hand-side ben given by b:= Hz* where r* :=|-1, 2, 3, 4, ...,(-1)"r)". Starting from xo := 0 apply the conjugate gradient method. Write a matrix-free MATLAB code, i.e, without storing any matrix. Print the forward relative errors || 2* - *||1 for k=0,..., 20. Note: In MATLAB the vector norm ||w|l1 can be computed with the command norm(v,1). 1 We consider the system of linear equations Hx = b given by the following symmetric (strictly) row-wise diagonally dominant and (strictly) positive definite matrix 4 1 4 1 H E Rnxn 1 0 0 1 4 0 1 0 0 1 0 0 4 1 0 4 1 1 4 of dimension n = 100 and right-hand-side ben given by b:= Hz* where r* :=|-1, 2, 3, 4, ...,(-1)"r)". Starting from xo := 0 apply the conjugate gradient method. Write a matrix-free MATLAB code, i.e, without storing any matrix. Print the forward relative errors || 2* - *||1 for k=0,..., 20. Note: In MATLAB the vector norm ||w|l1 can be computed with the command norm(v,1)