Answer to Question #43136 in MatLAB | Mathematica | MathCAD | Maple for Eric aung

Question

Solve the following systems of equations using both the matrix left divison and the inverse matrix methods:

(a) -2x1 + x2 = -3
x1 + x2 = 3

(b) 10x1 - 7x2 + 0x3 = 7
-3x1 + 2x2 + 6x3 = 4
5x1 + x2 + 5x3 = 6

(c) x1+ 4x2 - X3 + X4 = 2
2x1+ 7x2 +x3 -2x4 = 16
x1 + 4x2 - x3 + 2x4 = -15
3x1 - 10x2 -2x3 + 5x4 = -15

Answer 1

b1 = [-3;3];
A1 = [-2 1; 1 1];
x1 = A1\b1
b2=[7; 4; 6];
A2=[10 -1 0;-3 2 6; 5 1 5];
x2=A2\b2
b3=[-2; 16; -15; -15];
A3=[1 4 -1 1;2 7 1 -2; 1 4 -1 2; 3 -10 -2 5];
x3=A3\b3
x1 =
2
1
x2 =
-2.4000
-31.0000
9.8000
x3 =
5.0154
-1.2769
-11.0923
-13.0000