Higher Education · Pure Mathematics
Number Theory
What is it
Undergraduate number theory studies the properties of integers in depth — covering divisibility, prime numbers, modular arithmetic, and the proofs behind results like the Fundamental Theorem of Arithmetic.
Why it matters
Number theory, once considered 'pure' mathematics with no practical use, is now the mathematical foundation of modern cryptography — the RSA encryption that secures online banking and messaging relies directly on properties of prime numbers studied here.
Exam tip
Get comfortable with modular arithmetic notation (like a ≡ b (mod n)) early — it appears throughout number theory proofs, and treating it as a new kind of 'equals sign' with its own rules makes later proofs far more approachable.
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