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
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
