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Topic: Simple versus formal proof?
Replies: 34   Last Post: Jun 26, 2006 4:54 AM

 Messages: [ Previous | Next ]
 Ross Clement Posts: 569 Registered: 12/8/04
Re: Simple versus formal proof?
Posted: Jun 23, 2006 10:04 AM

Mohab wrote:
> not so, what if you go negative?
> (k-1)^2 + (k-1)

Factorise k^2 + k as k(k+1). Substituting k-1 for k gives (k-1)k, and
the previous proof that since one of these is odd and the other even
therefore the product is even holds. Of course this form of proof could
be used to prove the theorem for all k, so it really shows up how proof
by induction is unneccessary for this problem, but it would still be a
valid proof by induction would it not?

Cheers,

Ross-c

Date Subject Author
6/23/06 Ross Clement
6/23/06 William Elliot
6/23/06 Ross Clement
6/23/06 William Elliot
6/23/06 Ross Clement
6/23/06 tamiry
6/23/06 Ross Clement
6/23/06 Robert Low
6/23/06 Ross Clement
6/23/06 Robert Low
6/23/06 The Qurqirish Dragon
6/23/06 Ross Clement
6/25/06 K. E. Pledger
6/26/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Robert Low
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Tom Smith
6/23/06 Tom Smith
6/23/06 Bob Marlow
6/23/06 Robert Low
6/23/06 Bob Marlow
6/23/06 Robert Low
6/24/06 Bob Marlow
6/23/06 tamiry
6/23/06 Justin
6/23/06 Tom Smith
6/23/06 Bob Marlow
6/23/06 Tom Smith
6/23/06 Bob Marlow