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Extra -2 Review of Linear Systems. By: Prof. Y. Peter Chiu 9 / 2011. § . L 23 : Cramer’s Rule A‧X = B X = B =. § . L 23 : Cramer’s Rule. X = A -1 B x i =.
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Extra -2Review of Linear Systems By: Prof. Y. Peter Chiu 9 / 2011
§ . L 23 : Cramer’s Rule A‧X = B X = B =
§ . L 23 : Cramer’s Rule X = A-1B xi=
Example 23-1 -2X1 + 3X2 - X3= 1 X1 + 2X2 - X3 = 4 X1= -2X1 - X2 + X3=-3 B→ X1= B→ B
§ . L 24 : If ≠ 0 Then ① A-1 exist ② Linear System has nontrivial solution. (非 0 解) ③ rank A = n ④ The rows (columns) of A are linearly independent.
§ . L 25 : Gaussian Elimination高斯消去法 上三角(upper triangular)
§ . L 27 : Homework #1 X1+ X2 + 2X3 =-1 X1- 2X2 + X3 =-5 3X1+ X2 + X3 = 3 (a) Using Gaussian Elimination method to find solution. (b) Using Gauss-Jordan reduction method. (c) Using Cramer’s rule #2 2X1+ 4X2 + 6X3 = 2 X1+ 2X3 = 0 2X1+ 3X2 - X3 =-5 Using Cramer’s rule to solve it.
§ . L 27 : Homework #3 Solve 3 X1- X2= 3 #4 Solve2X1+ X2 +3X3 = 2 X1+ X3= 1 #5SolveX1+ 2X2 +3X3 = 6 4X1+ X3 = 4 2X1+ 4X2 +6X3 = 11