Induction and Recursion (Handout)
Worked handout: the ladder and domino intuition, the basis step and inductive step, solved induction proofs for sums, divisibility and inequalities, and recursively defined functions.
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All 34 slides
- 1 Mathematical Induction 5.1 & 5.3
- 2 1. We can reach the first rung of the ladder. 2. If we can reach a particular rung of the ladder, then we can reach the next rung.
- 3 Principle of Mathematical Induction: To prove that P(n) is true for all positive integers n, where P(n) is a propositional function,
- 4 Induction Works - Domino Effect
- 5 Slide 5
- 6 Slide 6
- 7 Mathematical Induction
- 8 Slide 8
- 9 Slide 9
- 10 Slide 10
- 11 Slide 11
- 12 Slide 12
- 13 Slide 13
- 14 Slide 14
- 15 Slide 15
- 16 Slide 16
- 17 Slide 17
- 18 Slide 18
- 19 Slide 19
- 20 k k
- 21 Slide 21
- 22 Slide 22
- 23 Slide 23
- 24 Slide 24
- 25 Slide 25
- 26 Recursively Defined Functions
- 27 Slide 27
- 28 Slide 28
- 29 Slide 29
- 30 Slide 30
- 31 Slide 31
- 32 Example 4
- 33 Example 5
- 34 Slide 34
Induction Works - Domino Effect
Notes
Dominoes: first falls + each one knocks the next ⇒ all fall.
Mathematical Induction
Notes
Basis step: prove P(1) (or the first value). Inductive step: assume P(k) (the inductive hypothesis) and prove P(k + 1).
Trap In the inductive step you must USE P(k); just proving P(k + 1) from scratch is not induction.