归纳

本章主要学习数学中运用的归纳法。归纳在数学中有着非常重要的作用。本文举例说明了利用归纳来证明论题的方法。通归纳证明模板更好的学习了归纳法。
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1.Induction 2/24/12 1

2.The Idea of Induction Color the integers ≥ 0 0 , 1 , 2 , 3 , 4 , 5 , … I tell you, 0 is red , & any int next to a red integer is red , then you know that all the ints are red ! 2/24/12 2

3.Induction Rule 2/24/12 3

4.Like Dominos…

5.Example Induction Proof Let’s prove: (for r ≠ 1)

6.Statements in magenta form a template for inductive proofs: Proof: (by induction on n ) The induction hypothesis, P ( n ) , is: Example Induction Proof (for r ≠ 1)

7.Base Case ( n = 0 ) : Example Induction Proof 1 OK!

8.Inductive Step: Assume P ( n ) for some n ≥ 0 and prove P ( n+1 ) : Example Induction Proof

9.Now from induction hypothesis P ( n ) we have Example Induction Proof so add r n+1 to both sides

10.adding r n+1 to both sides, Example Induction Proof This proves P ( n+1 ) completing the proof by induction.

11.“  ” is an ellipsis . Can lead to confusion (n = 0 ?) Sum notation more precise Means you should see a pattern : an aside: ellipsis