Chapter II

Linear Algebra

This chapter is essentially devoted to the study of a particular type of commutative groups with operators (I, § 4, no. 2) called modules. Certain properties stated in §§ 1 and 2 for modules extend to all commutative groups with operators; these will be indicated as they occur. Moreover it will be seen in Chapter III, § 2, no. 6 that the study of a commutative group with operators is always equivalent to that of a module suitably associated with the group with operators in question.