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Question
If A is an m × n matrix and B is n × p matrix does AB exist? If yes, write its order.
Solution
Given: Order of A = \[m \times n\]
Order of B = \[n \times p\]
Since the number of columns in A are equal to the number of rows in B, i.e. n, AB exists.
Order of AB = Number of rows in A \[\times\] Number of columns in B
\[m \times p\]
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