4. Consider the matrix equation Ax = b where, where a, b 0. A 1 = (1 1). a b (a) When is A strictly diagonally dominant and what does this tell us about the Gaus Seidel method for Ax = b. [1 marks (b) Find the iteration matrix for the Gauss-Seidel method applied to Ax = b. [5 marks (c) Using your previous answers, for what values of a and b does the Gauss-Seidel metho converge. [4 marks