Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math

Topic: ----------- math reference
Replies: 3   Last Post: Aug 10, 2011 6:29 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Tim Little

Posts: 1,793
Registered: 2/7/09
Re: ----------- math reference
Posted: Aug 8, 2011 10:18 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On 2011-08-08, Deep <deepkdeb@yahoo.com> wrote:
> I would appreciate it very much if someone can refer me to an
> appropriate reference where following statement is justified.
>
> Statement: Every integer N that is not 2mod4 can be expressed as the
> difference of two squares.


No reference necessary.

For odd numbers: 2n+1 = (n+1)^2 - n^2.
For numbers divisible by 4: 4n = (n+1)^2 - (n-1)^2.

They may also have other representations, but these suffice to justify
the statement.


--
Tim



Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.