Don't have an account? Register now to chat, post, use our tools, and much more.
This is an archived, read-only copy of the United-TI subforum , including posts and topic from May 2003 to April 2012. If you would like to discuss any of the topics in this forum, you can visit Cemetech's Technology & Calculator Open Topic subforum. Some of these topics may also be directly-linked to active Cemetech topics. If you are a Cemetech member with a linked United-TI account, you can link United-TI topics here with your current Cemetech topics.

Math and Science => Technology & Calculator Open Topic
Author Message
Flofloflo

Member

Joined: 07 Nov 2007
Posts: 120

 Posted: 26 Feb 2009 06:59:26 am    Post subject: Hello, Searching for divisors I figured divisors of 2x can only be divided by other numbers that can be written as 2y, and I think that goes for other powers and stuff too, but it seems impossible to prove... Does anybody have a clue how to prove it?? I tried writing things as logaritms and all, but I suppose the only way to prove it is to use similar methods like proving sqrt(2) doesn't have divisors but we barely do that yet at school, so I have absolutely no idea how to start on this...
simplethinker
snjwffl

Active Member

Joined: 25 Jul 2006
Posts: 700

 Posted: 26 Feb 2009 11:01:47 am    Post subject: Think of it this way: Any integer can be written as N=p1a1p2a2...prar, where all the pr's are primes. A number M can only be a divisor of N if and only if its set prime factors is a subset of Ns prime factors and the exponents are less than or equal to the powers in N. For example, 360=233251. Any divisor D of 360 must then be of the form D=2b13b25b3 where 0≤b1≤3, 0≤b2≤2 and 0≤b3≤1 Quote:but I suppose the only way to prove it is to use similar methods like proving sqrt(2) doesn't have divisors but we barely do that yet at school, so I have absolutely no idea how to start on this... It's actually a different approach. With sqrt(2), you're dealing with the existence of factors, but with this you're dealing with the form of the factors.
Flofloflo

Member

Joined: 07 Nov 2007
Posts: 120

 Posted: 26 Feb 2009 02:37:13 pm    Post subject: Okay, thanks! It keeps amazing me how much stuff you can do with primes:P
 Display posts from previous: All Posts Oldest FirstNewest First
Register to Join the Conversation
Have your own thoughts to add to this or any other topic? Want to ask a question, offer a suggestion, share your own programs and projects, upload a file to the file archives, get help with calculator and computer programming, or simply chat with like-minded coders and tech and calculator enthusiasts via the site-wide AJAX SAX widget? Registration for a free Cemetech account only takes a minute.

»
 Page 1 of 1 » All times are GMT - 5 Hours