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

How do you rationalize fractions

  1. Jan 30, 2007 #1
    how do you do that
     
  2. jcsd
  3. Jan 30, 2007 #2
  4. Jan 31, 2007 #3

    arildno

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    Incorrect!
    A "fraction" is a real number that is written as the product of one real number a (called the "numerator"), and the multiplicative inverse of a real (non-zero) number b (called the denominator).

    To "rationalize" a fraction means to rewrite the denominator as a natural number, if possible.

    Example:
    [tex]\frac{1}{\sqrt{2}}=\frac{1}{\sqrt{2}}*1=\frac{1}{\sqrt{2}}*\frac{\sqrt{2}}{\sqrt{2}}=\frac{\sqrt{2}}{2}[/tex]
     
  5. Jan 31, 2007 #4

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    What does this have to do with calculus? I am moving it to "General Math".
     
  6. Jan 31, 2007 #5

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    I've never heard of "realizing" a fraction! What language is that translated from? However, I will agree that one does not rationalize fractions!
    The example arildno gave was rationalizing the denominator of a fraction. There are also times when one would want to rationalize the numerator of a fraction. In general, it is not possible to rationalize both numerator and denominator at the same time.
     
  7. Jan 31, 2007 #6
    My apologies! I've made a big fool of myself once again. I was thinking about "realising" as in making the denominator of a fraction (containing complex numbers) real! (I was taught this term back in high school, here in Australia.) arildno and Hallsofivy are absolutely correct.

    I'm really sorry for wasting everyone's time. I think I should go back to lurking. :blushing:
     
  8. Feb 1, 2007 #7

    arildno

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    I stand corrected.
     
  9. Feb 1, 2007 #8

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    "realizing"! I like that. Reminds me of when, in an algebra class, we were learning about 'adding' an identity to a semigroup (to make it a monoid) and we had quite an argument about what the process should be called.

    Suggestions were "unification", "one-ification" and "identification"!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: How do you rationalize fractions
  1. How do you prove this? (Replies: 10)

Loading...