Proving the Binomial Identity: A Shorter Solution Approach

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    Binomial Identity
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Homework Help Overview

The discussion revolves around proving a binomial identity involving binomial coefficients, specifically the identity that relates the coefficients of powers of 2. The subject area is combinatorics, focusing on binomial coefficients and their properties.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to find a shorter proof than induction and suggests a connection between the right-hand side of the identity and the square of a sum of binomial coefficients. Other participants question the effectiveness of their approaches and suggest alternative methods, such as expanding a binomial expression.

Discussion Status

The discussion is ongoing, with participants exploring different methods to approach the proof. Some guidance has been offered regarding the expansion of binomial expressions, but no consensus or definitive solution has emerged yet.

Contextual Notes

There is an indication that the original poster may be struggling with the complexity of induction and is seeking a more straightforward method. The discussion also reflects a potential lack of familiarity with binomial coefficients among some participants.

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problem
prove that:
[tex]\forall n \in N \forall 0<=k<=2^{n-1} (C(2^n,k)=\sum_{j=0}^{k}C(2^{n-1},j)C(2^{n-1},k-j))[/tex]

attempt at solution
induction seems to be too long I am opting for a shorter solution, so the sum that it's wrriten in the rhs is the square of the sum of the term C(2^(n-1),j) but other than that don't know how to procceed.

any advice?

thanks in advance.
 
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C is the binomial coefficient.
 
so i guess no one here is that good with B.Cs?
 
Have you tried using the fact that [tex]2^n=2^{n-1}+2^{n-1}[/tex]
Then expand [tex](1+x)^{2^n}[/tex] in two different ways, equating coefficients of [tex]x^k[/tex]?
 

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