Discrete Math

Study of mathematical structures that are fundamentally discrete rather than continuous.

Basic Concepts

Functions and Relations

Functions

A function is like a machine that takes an input and produces exactly one output. In discrete math, functions help describe how elements from one set are related to elements in another.

Relations

A relation shows how elements from two sets are connected. For example, "is taller than" is a relation between people.

Properties of Functions

  • One-to-One (Injective): Each input has a unique output.
  • Onto (Surjective): Every output value is used.
  • Bijective: Both one-to-one and onto.

Importance

Functions and relations help us organize information, model processes, and solve real-world problems in computer science and data analysis.

Examples

  • Assigning a student to their unique ID number is a function.

  • 'Is a sibling of' is a relation among people.

In a Nutshell

Functions connect inputs to unique outputs, while relations describe connections between elements from sets.