Search results
Results from the WOW.Com Content Network
Mathematical induction can be informally illustrated by reference to the sequential effect of falling dominoes. [1] [2]Mathematical induction is a method for proving that a statement () is true for every natural number, that is, that the infinitely many cases (), (), (), (), … all hold.
We prove commutativity (a + b = b + a) by applying induction on the natural number b. First we prove the base cases b = 0 and b = S(0) = 1 (i.e. we prove that 0 and 1 commute with everything). The base case b = 0 follows immediately from the identity element property (0 is an additive identity), which has been proved above: a + 0 = a = 0 + a.
For example, we can prove by induction that all positive integers of the form 2n − 1 are odd. Let P(n) represent "2n − 1 is odd": (i) For n = 1, 2n − 1 = 2(1) − 1 = 1, and 1 is odd, since it leaves a remainder of 1 when divided by 2. Thus P(1) is true.
English: Shows recursive definitions of addition (+) and multiplication (*) on natural numbers and inductive proofs of commutativity, associativity, distributivity by Peano induction; also indicates which property is used in the proof of which other one.
Structural induction is a proof method that is used in mathematical logic (e.g., in the proof of Łoś' theorem), computer science, graph theory, and some other mathematical fields. It is a generalization of mathematical induction over natural numbers and can be further generalized to arbitrary Noetherian induction .
Proof by exhaustion can be used to prove that if an integer is a perfect cube, then it must be either a multiple of 9, 1 more than a multiple of 9, or 1 less than a multiple of 9. [3] Proof: Each perfect cube is the cube of some integer n, where n is either a multiple of 3, 1 more than a multiple of 3, or 1 less than a multiple of 3. So these ...
We prove the theorem by induction on the proof length n; thus the induction hypothesis is that for any , and such that there is a proof of from {} of length up to n, holds. If n = 1 then B {\displaystyle B} is member of the set of formulas Δ ∪ { A } {\displaystyle \Delta \cup \{A\}} .
For any n ≥ 2, the function T n (x) has exactly n fixed points. Proof. There are 3 fixed points in the illustration above, and the same sort of geometrical argument applies for any n ≥ 2. Lemma 2. For any positive integers n and m, and any 0 ≤ x ≤ 1, (()) = ().