Theorem 3.7. (Elementary Transformations). The following opera- tions applied to a linear system yield an equivalent system: ()Interchange: The order of two equations can be changed. (2)Scaling: Multiplying an equation by a nonzero constant. (3)Replacement: An equation can be replaced by the sum of itself and a nonzero multiple of any other equation
1 Mathematical Preliminaries and Error Analysis 2 Solutions of Equations in One Variable 3 Interpolation and Polynomial Approximation 4 Numerical Differentiation and Integration 5 Initial-Value Problems for Ordinary Differential Equations 6 Direct Methods for Solving Linear Systems 7 IterativeTechniques in Matrix Algebra 8 ApproximationTheory 9 Approximating Eigenvalues 10 Numerical Solutions of Nonlinear Systems of Equations 11 Boundary-Value Problems for Ordinary Differential Equations 12 Numerical Solutions to Partial Differential Equations
第三章解线性方程组的直接法 Direct Method for Solving Linear Systems 求解A=万 1高斯消元法Gaussian Elimination*1 高斯消元法思首先将A化为上三角阵l*uper--triangular matrix*1路,再回代求解l* backward substitution*1