Modular Arithmetic

Introduction to Congruences

Congruences explore the number left over after division.
Requirements: Divisibility Difficulty: 2

Solving Linear Congruences

Solving for x in $ax ≡ b(mod n)$.
Requirements: Bézout's Identity Difficulty: 3

The Chinese Remainder Theorem

Solving systems of simultaneous congruences.
Requirements: Linear Congruences Difficulty: 3

Properties of Congruences

Defining Mathematical Operations mod m.
Requirements: Linear Congruences Difficulty: 3

Divisibility Tests

Finally, a proof for why divisibility rules work!
Requirements: Congruences Difficulty: 2

Euler's Totient Function

Counting numbers coprime to n.
Requirements: Primes Difficulty: 3

The Order of an Integer

How many times do you multiply before you get back to 1?
Requirements: Euler's Totient Function Difficulty: 3

Primitive Roots

Integers that can generate all others (mod p).
Requirements: Euler's Theorem Difficulty: 4

Quadratic Residues

Numbers that have square roots modulo n.
Requirements: Modular Arithmetic Difficulty: 4
⬅️ Back