# Mathedu

Learn math by practice

The Section 4 of our Math Course is about the Multiplication between Relative Integers.

### Lecture 7: Multiplication Exploration

The multiplication between positive integers is a 'long' addition at first glance.

But in Scilab, it is the operator '*', that may be used to multiply any relative integers with different signs, and even 0!

The 'signs rules' for the multiplication are given, after we have explored it in Scilab.

### Quiz 5: Multiply Relative Integers

That little Quiz assesses the knoledge of the signs rules, as well as the multiplication by the particular numbers 0, 1 and -1.

### Lecture 8: The Ring of Relative Integers with the Addition and the Multiplication

The relative integers set Z has, together with the addition and the multiplication, a so called structure of "ring". This lecture explains the characteristic properties of a ring, always beginning with examples.

There are 2 additional pdf files. "ZplusMultRing" explains more completely the structure of ring and its consequences, in particular the role of parentheses in a formula.

The second pdf file is a serie of solved exercises using the properties of the multiplication together with the addition.