Question:
Write the number of all possible matrices of order $2 \times 2$ 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 $3 \times 3 \times 3 \times 3$ i.e, $3^{4}$ times or 81 times.