Noyau d'un morphisme de groupes

We define the notion of the kernel of a group homomorphism and establish some elementary properties of it. Chapter XIII, Part 2.3 (https://mpsilamartin.github.io/maths/...) 0:00 Introduction 0:35 Theorem (Image and Pull-Back of a Subgroup by a Homomorphism) 13:47 Definition of Kernel 15:20 Subgroup Structure of the Kernel and Image 19:12 Examples 24:00 Fundamental Lemma 30:38 Characterization of the Injectivity of a Homomorphism