Proof Writing & Problem Solving
Proof
How to read, find and write a proof: direct proof, contrapositive and contradiction, induction, pigeonhole and extremal arguments, quantifiers and counterexamples, problem-solving strategy, and the craft of writing it up.
What you'll be able to do
- Write a correct, complete proof in full sentences
- Choose the right proof technique for a claim
- Find proofs with small cases, working backwards and invariants
- Audit a proof for gaps
Start the course
Go through each topic step by step — prose, worked examples, quick checks, and a timed practice round after every section.
Practice writing proofsRandom proof practice Final Test (30) Big Test (50) Search & glossary Flashcards Print the course (PDF)Suggest a problem
Every test ends with a score by topic and a list of what to revisit. Test out of a topic with 80% or better to mark it mastered.