Answer:
AB = ![\left[\begin{array}{ccc}-3&4&6\\-6&3&5\\5&0&-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-3%264%266%5C%5C-6%263%265%5C%5C5%260%26-4%5Cend%7Barray%7D%5Cright%5D)
Each column of AB is written as a linear combination of columns of Matrix A in the explanation below.
Step-by-step explanation:
A = ![\left[\begin{array}{ccc}-2&2&1\\-3&1&1\\2&0&-1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%262%261%5C%5C-3%261%261%5C%5C2%260%26-1%5Cend%7Barray%7D%5Cright%5D)
B= ![\left[\begin{array}{ccc}2&-1&0\\1&2&1\\-1&-2&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%26-1%260%5C%5C1%262%261%5C%5C-1%26-2%264%5Cend%7Barray%7D%5Cright%5D)
We need to write each column of AB as a linear combination of the columns of A so we will multiply each column of A with each column element of B to get the column of AB. So,
AB Column 1 = 2 *
+ 1
+ (-1)
= ![\left[\begin{array}{ccc}-3\\-6\\5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-3%5C%5C-6%5C%5C5%5Cend%7Barray%7D%5Cright%5D)
AB Column 2 = (-1)
+ 2
+ (-2)
= ![\left[\begin{array}{ccc}4\\3\\0\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%5C%5C3%5C%5C0%5Cend%7Barray%7D%5Cright%5D)
AB Column 3 = (0)
+ (1)
+ 4
= ![\left[\begin{array}{ccc}6\\5\\-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D6%5C%5C5%5C%5C-4%5Cend%7Barray%7D%5Cright%5D)
Finally, we can combine all three columns of AB to form the 3x3 matrix AB.
AB = ![\left[\begin{array}{ccc}-3&4&6\\-6&3&5\\5&0&-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-3%264%266%5C%5C-6%263%265%5C%5C5%260%26-4%5Cend%7Barray%7D%5Cright%5D)