What is a semi-direct product? - Semi-direct products - Part 1

We define a complement of a subgroup N of G, then examine multiplication in G to show that an internal semi-direct product occurs as a generalization of the internal direct product. 0:00 Complements of subgroups 2:38 Internal products of groups 4:54 Internal direct product 7:15 Internal semi-direct product 9:15 Internal Zappa-Szép product #math #maths #grouptheory