Question

Determine whether the product of the matrices is defined in each case. If so, state the order of the product. PQ, where $P=[p_{ij}{]}_{4\times 3},Q=[q_{ij}{]}_{4\times 3}$

Answer 1

$P={\left[p_{ij}\right]}_{4\times 3},Q={\left[q_{ij}\right]}_{4\times 3}$

Number of column of $P\ne$ number of rows of $Q$

$\therefore PQ$ is not defined.

Hence, the answer is $PQ$ is not defined.