4.1 BACKGROUND4.2 GAUSS ELIMINATION METHOD4.3 GAUSS ELIMINATION WITH PIVOTING4.4 GAUSS–JORDAN ELIMINATION METHOD4.5 LU DECOMPOSITION METHOD4.6 INVERSE OF A MATRIX4.7 ITERATIVE METHODS4.8 USE OF MATLAB BUILT-IN FUNCTIONS FOR SOLVING A SYSTEM OF LINEAR EQUATIONS4.9 TRIDIAGONAL SYSTEMS OF EQUATIONS4.10 ERROR, RESIDUAL, NORMS, AND CONDITION NUMBER4.11 ILL-CONDITIONED SYSTEMS4.12 PROBLEMS