Editing Geometry (section)

==Set theory==
[[File:LawsOfSets.png|thumb|Laws of set theory]]

[https://www.youtube.com/watch?v=AAJB9l-HAZs&list=PLPH7f_7ZlzxTi6kS4vCmv4ZKm9u8g5yic&index=2 Lecture 02]

[https://www.youtube.com/watch?v=6EIWRg-6ftQ&list=PLPH7f_7ZlzxTi6kS4vCmv4ZKm9u8g5yic&index=3 Lecture 03]

epsilon-relation (member relation); Zermelo-Fraenkel axioms of set theory; Russel's paradox; existence and uniqueness of the empty set (standard textbook proof and formal proof); axioms on the existence of pair sets and union sets; examples; finite unions; functional relation and image; principle of restricted and universal comprehension; axiom of replacement; intersection and relative complement; power sets; infinity; the sets of natural and real numbers; axiom of choice; axiom of foundation.

definition of maps (or functions) between sets; structure-preserving maps; identity map; domain, target and image; injective, surjective and bijective maps; isomorphic sets; classification of sets: finite and countably and uncountably infinite; cardinality of a set; composition of maps; commutative diagrams; proof of associativity of composition; inverse map; definition of pre-image and properties of pre-images (with proof); equivalence relations: reflexivity,  symmetry, transitivity; examples; equivalence classes and quotient set; well-defined maps; construction of ℕ, ℤ, ℚ, ℝ (natural, integer, rational and real numbers); successor and predecessor maps; nth power set; addition and multiplication of numbers; canonical embeddings.