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Question
Write the number of all possible matrices of order 2 × 2 with each entry 1, 2 or 3.
Solution
As matrices is of order 2 × 2, so there are 4 entries possible.
Each entry has 3 choices that are 1, 2 or 3
So, number of ways to make up such matrices are 3 × 3 × 3 × 3 i.e, 34 times or 81 times.
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