ext{if} \quad A = \begin{bmatrix} 1 & 2 \ 3 & 4 \end{bmatrix}, \quad B = \begin{bmatrix} 0 & 1 \ 1 & 0 \end{bmatrix} \quad ext{, what is AB} \quad

Python

import numpy as np

A = np.array([[ 1 , 0 , 0 , 0 ], [ 0 , 2 , 0 , 0 ], [ 0 , 0 , 3 , - 1 ], [ 0 , 0 , 0 , 4 ]])
B = np.array([[ 3 , 0 , 0 , 0 ], [ 0 , 3 , 0 , 0 ], [ 0 , 0 , 3 , - 2 ], [ 0 , 0 , 0 , 1 ]])

det_A = np.linalg.det(A)
det_B = np.linalg.det(B)

print( f" {det_A=} " )
print( f" {det_B=} " )

Code output
det_A=23.999999999999993
det_B=27.0

Question

ext{if} \quad A = \begin{bmatrix} 1 & 2 \ 3 & 4 \end{bmatrix}, \quad B = \begin{bmatrix} 0 & 1 \ 1 & 0 \end{bmatrix} \quad 	ext{, what is AB} \quad

Python

import  numpy  as  np

A = np.array([[ 1 ,  0 ,  0 ,  0 ], [ 0 ,  2 ,  0 ,  0 ], [ 0 ,  0 ,  3 , - 1 ], [ 0 ,  0 ,  0 ,  4 ]])
B = np.array([[ 3 ,  0 ,  0 ,  0 ], [ 0 ,  3 ,  0 ,  0 ], [ 0 ,  0 ,  3 , - 2 ], [ 0 ,  0 ,  0 ,  1 ]])

det_A = np.linalg.det(A)
det_B = np.linalg.det(B)

print( f" {det_A=} " )
print( f" {det_B=} " )

Code output 
 det_A=23.999999999999993
det_B=27.0

Answer

\begin{bmatrix} 2 & 1 \ 4 & 3 \end{bmatrix}

Answer

\begin{bmatrix} 1 & 2 \ 4 & 3 \end{bmatrix}

Answer

\begin{bmatrix} 2 & 1 \ 1 & 4 \end{bmatrix}

Answer

\begin{bmatrix} 1 & 0 \ 0 & 1 \end{bmatrix}

Crowdly

\text{if} \quad A = \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}, \quad B =...

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