MathGloss

For AA an m×nm\times n matrix and BB an n×pn\times p matrix with entries (aij)(a_{ij}) and (bk)(b_{k\ell}) respectively, the product C=ABC=AB is the m×pm\times p matrix whose entries are given by cij=k=1naikbkjc_{ij} = \sum_{k=1}^n a_{ik}b_{kj} for 1im1 \leq i \leq m and 1jm1 \leq j \leq m.

Note that this binary operation is not commutative, and BABA may not even be defined even though ABAB is due to differing dimensions.

Wikidata ID: Q1049914