Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Rational Numbers

  1. Sep 17, 2006 #1
    Is the number 1, or any other whole/negative number a rational number?
     
  2. jcsd
  3. Sep 17, 2006 #2

    radou

    User Avatar
    Homework Helper

    Every integer is a rational number, since for every integer a you can write a = a / 1. The set of integers is a subset of the set of rational numbers.
     
  4. Sep 17, 2006 #3
    Alright thanks alot =).. so both negative and positive intgers are rational, also any fraction?... would the square root of 13 be classified as rational?
     
  5. Sep 17, 2006 #4

    radou

    User Avatar
    Homework Helper

    Find the definition of a rational number on the internet (or on this forum), it will clear some things up. :smile:
     
  6. Sep 17, 2006 #5
    i think the square root of any number that isn't a perfect square is irrational.... maybe the square root of any power whose exponent is a power of 2 is rational. the square root of a prime is irrational for sure, & i think that can be proven the same way the square root of 2 is proven irrational.
     
  7. Sep 17, 2006 #6

    shmoe

    User Avatar
    Science Advisor
    Homework Helper

    the square root of 13 is irrational. For a natural number n, sqrt(n) is rational if and only if n=m^2 for some natural number m.

    Similar statement for kth roots, n^(1/k) is rational if and only if n=m^k.
     
  8. Sep 17, 2006 #7

    kar

    User Avatar

    The definition of a rational number is: a number that can be expresed as a fraction p/q, where p and q are integers, q is not equal to 0.
    Thus, any integer (positive and negative) is a rational number.
    As for sqrt(13) - you can try and prove that it is not a rational number.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Rational Numbers
Loading...