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Question
Let `A = [(2,4),(3,2)] , B = [(1,3),(-2,5)], C = [(-2,5),(3,4)]`
Find BA
Solution
Matrix B has 2 columns. This number is equal to the number of rows in matrix A. Therefore, BA is defined as:
`BA = [(1,3),(-2,5)][(2,4),(3,2)]`
=`[(1(2)+3(3), 1(4)+3(2)), (-2(2)+5(3), -2(4)+5(2))]`
=`[(2+9, 4+6), (-4+15, -8+10)]`
=`[(11,10),(11,2)]`
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