Mathematical Induction Framework & History and How it works

Vishvdeep Dasadiya
5 min readSep 23, 2021

Framework for Mathematical Induction

  1. Express the statement that is to be proved in the form “for all n ≥ b, P(n)” for a fixed integer b.
  2. Write out the words “Basis Step”. Then show that P(b) is true, taking care that the right value of b is employed . This completes the primary a part of the proof.
  3. Write out the words “Inductive Step”.
  4. State, and clearly Identify, the inductive hypothesis, within the form “assume that P(k) is true for an arbitrary fixed integer k ≥ b”.
  5. State what must be proved under the idea that the inductive hypothesis is true. That is, write out what P(k+1) says.
  6. Prove the statement P(k+1) making use the idea P(k). make certain that your proof is valid for all integers k with k ≥ b, taking care that the proof works for little value of k, including k = b.
  7. Clearly identify the conclusion of the inductive step, like by saying “this completes the inductive step.”
  8. After completing the basic step and therefore the inductive step, state the conclusion, namely that by mathematical induction, P(n) is true for all integers n with n ≥ b.
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History

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The first known use of mathematical induction is within the work of the sixteenth-century mathematician Francesco Maurolico (1494 –1575). Maurolico wrote extensively on the works of classical mathematics and made many contributions to geometry and optics.

During this boom Arithmeicorum Libri Duo, Maurolico presented a spread of properties of the integers togethers with proofs of those properties.

To prove some fo these properties, he devised the tactic of mathematical induction. His first use of mathematical induction during this book was to prove that the sum of the primary n odd positive integers equals n².

Augusus De Morgan is credited with the primary presentation in 1838 formal proofs using mathematical induction, also as introducing the terminology “Mathematical induction”. Maurolico’s proofs were informal and he never used the word “Induction”. The name induction was employed by English mathematician John Wallis.

Remember how mathematical Induction works

Imagine the infinite ladder and therefore the rules for reaching steps can assist you understand and visualise how mathematical induction works.

Important to notice down that statements [1] and [2] for the infinite ladder are precisely the basis step and inductive step, respectively. The proof that P(n) is true for all positive integers n, where P(n) is that the statement that we will reach the nth rung of the ladder. Therefore, we will invoke mathematical induction to conclude that we will reach every rung.

Why Mathematical Induction is Valid?

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Why is mathematical induction a legitimate proof technique? Why mathematician use tons mathematical induction for proving results. the rationale comes form the well-ordering property of the induction. as an example , the set of positive integers, which states that each nonempty subset of the set of positive integers features a lest element. Therefore, suppose we all know that P(1) is true which the proposition P(k) -> P(k+1) is true for all positive integers k.

To prove that P(n) must be true for all positive integers n, assume that there’s at lest one positive integer that P(n) is false . Then the set S of positive integers that P(n) is false is nonempty. Therefore, by the well-ordering property, S features a least element, which can be denoted by m. we all know that m can’t be 1, because P(1) is true. Because m is positive and greater than 1, m-1 may be a positive integer.

Furthermore, because m-1 is a smaller amount than m, it’s not in S, so P(m-1) must be true. Because the condition statement P(m-1) -> P(m) is additionally true, It must be the case that P(m) is true. This contradicts the selection of m. Hence, P(n) must be true for each positive integer n.

The positive and negative of Mathematical Induction

A vital point must be made about mathematical induction before we begin a study of its usage.

The positive thing about the mathematical induction is that it are often wont to prove a conjecture once it’s been made. On the opposite side, negative thing about the it’s that it can’t be wont to find new theorems.

Mathematicians or scientist sometimes find proofs by mathematical induction unsatisfying because they are doing not provide information on why theorems are true.

Many theorems are often proved in some ways , like one equation or formula are often interpret by geometrically, algebraic stand point, probabilistically, and Machine Learning optimisation stand point, that including by mathematical induction. Proofs of those theorems by methods aside from mathematical induction are often preferred due to the insights of the theorems they carry with the results.

Conclusion

One key point of mathematical thinking is deduction . Opposite to deduction, generalisation depends on working with different kinds of cases and developing a conjecture by observing incidences till we’ve observed each and each case. Therefore, in simple and straightforward language we will say the word “INDUCTION” means the generalisation from particular cases or facts.

The principle of mathematical induction is one such tool which may be wont to prove a good sort of mathematical statements. Each such statement is assumed as P(n) related to positive integer n, that the correctness for the case n=1 is examined. Then assuming the reality of P(k) for a few positive integer k, the reality of P(k+1) is established.

Content Reference and text reference used in this article are mentioned below:

https://ncert.nic.in/textbook/pdf/kemh104.pdf

Discrete Mathematics and its Applications by Keneth H. Rosen (Seventh Edition) [Book]

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