A Gentle Introduction to the Art of Mathematics
Preamble
Preface
- To the student
- To the instructor
1 Introduction and notation
2 Logic and quantifiers
3 Proof techniques I — Standard methods
4 Sets
5 Proof techniques II — Induction
6 Relations and functions
7 Proof techniques III — Combinatorics
8 Cardinality
9 Proof techniques IV — Magic
References
Published with bookdown

A Gentle Introduction to the Art of Mathematics

Chapter 6 Relations and functions

If evolution really works, how come mothers only have two hands?

—Milton Berle