# Discrete Math 1: Set Theory

## Cheat Sheet

# 1. Definitions

// Set A contains elements 1,2 and 3

A = {1,2,3}// 2 is an element of A

2∈A// 4 is not an element of A

4∉A

# 2. Number Sets

`Naturals N = {1,2,3,4,...}`

Integers Z = {...,-2,-1,0,1,2,...}

Rationals Q = Ratio of 2 integers…