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Quiz: Proof Techniques

5 questionsNo time limitPass: 60%+10 XP on first pass

How to prove things in discrete maths and why programmers care: direct proofs, proof by contrapositive and contradiction (√2 is irrational, infinitely many primes), mathematical induction step by step, strong induction, loop invariants, and the pigeonhole principle with real examples.

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  1. Question 1

    What are the two parts of a proof by mathematical induction?

  2. Question 2

    For which values did 2^n > n^2 fail in the demo (n = 1..10)?

  3. Question 3

    Proving "if n² is even then n is even" by showing "if n is odd then n² is odd" is a proof by:

  4. Question 4

    At least how many of 50 students share a birth month?

  5. Question 5

    A loop invariant is: