import numpy as np
A = np.matrix('1 1 0; 0 1 1; 1 0 1')
A
matrix([[1, 1, 0], [0, 1, 1], [1, 0, 1]])
v1=np.matrix('6; 7; 9')
v1
matrix([[6], [7], [9]])
invA = np.linalg.inv(A)
invA
matrix([[ 0.5, -0.5, 0.5], [ 0.5, 0.5, -0.5], [-0.5, 0.5, 0.5]])
invA.dot(v1)
matrix([[ 4.], [ 2.], [ 5.]])
v2=np.matrix('15; 13; 18')
invA.dot(v2)
matrix([[ 10.], [ 5.], [ 8.]])