Proving an equality using induction proof not working

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Homework Help Overview

The discussion revolves around proving an equality using induction, specifically focusing on a product involving two variables, n and k. Participants are exploring the challenges associated with this type of induction proof.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the inductive hypothesis and the necessary steps to prove the statement for k = m+1. There are questions about the clarity of the induction step and the need for additional parentheses in expressions. Some participants also question whether induction is the required method for this proof, suggesting that direct simplification might be easier.

Discussion Status

The discussion is ongoing, with various approaches being considered. Some participants are providing guidance on the induction process, while others are exploring alternative methods. There is no explicit consensus on the best approach yet.

Contextual Notes

Participants are working with a specific product and its properties, and there is mention of a jpeg image that contains part of the problem setup. The requirement to use induction is also being questioned, indicating potential constraints in the problem-solving approach.

tony700
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Homework Statement


I work out the problem completely and it does not equal out. Having problems with two variable induction proofs (n and k) in this problem. Below is as far as I got, jpeg below

Homework Equations

The Attempt at a Solution

 

Attachments

  • induction.jpg
    induction.jpg
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Our inductive hypothesis is ##\prod\limits_{n=1}^{k}n(2k+2-2n)=2^k(k!)^2##, for some ##k\in\{1,2,...\}##.

We want to show that ##\prod\limits_{n=1}^{k+1}n(2(k+1)+2-2n)=2^{k+1}((k+1)!)^2##.
 
tony700 said:

Homework Statement


I work out the problem completely and it does not equal out. Having problems with two variable induction proofs (n and k) in this problem. Below is as far as I got, jpeg below

Homework Equations

The Attempt at a Solution

upload_2016-1-3_22-26-12.png

That's what you're to prove.

I think it's clearer if you do the induction step as follows.

Assume that ##\displaystyle \ \prod_{n=1}^{k}n(2k+2-2n)=2^k(k!)^2 \ ## is true for ##\ k=m\ ## for some ##m>0##. Then show that it's true for ##k = m+1##. You must replace every ##k## with ##m## or ##m+1## as appropriate.

Note: In the jpeg image that you showed, you needed to have extra parentheses in a number of places.
 
tony700 said:

Homework Statement


I work out the problem completely and it does not equal out. Having problems with two variable induction proofs (n and k) in this problem. Below is as far as I got, jpeg below

Homework Equations

The Attempt at a Solution

Are you absolutely required to use induction? If not, just writing out the product directly and simplifying is by far the easiest way to do the problem.
 

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