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Question
Compute the products AB and BA whichever exists in each of the following cases:
`A=[[3 2],[-1 0],[-1 1]]` and `B= [[4 5 6],[0 1 2]]`
Solution
`AB=[[3 2],[-1 0],[-1 1]]``[[4 5 6],[0 1 2]]`
`⇒AB = [[ 12+0 15+2 18+4],[-4+0 -5+0 -6+0],[-4+0 -5+1 -6+2]]`
`⇒AB=[[12 17 22],[-4 -5 -6],[-4 -4 -4]]`
Also
`BA=[[4 5 6],[0 1 2]]` `[[3 2],[-1 0],[-1 1]]`
`⇒BA=[[12-5-6 8+0+6],[0-1-2 0+0+2]]`
`⇒BA=[[1 14],[-3 2]]`
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