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Using divide as a 'sign' for a number

  1. Aug 20, 2010 #1
    A negative number has the minus sign as its own intrinsic operator. Has anyone thought of using the divide symbol in a similar way, and has there been any attempt to standardize this throughout math?

    For example (assuming / is the divide symbol):
    /5 = reciprocal of 5 = 1/5 = 0.2.

    It saves having to always use the "1 divided by" bit in 1/x.

    One can then even use two divides to cancel each other out. Example: //5 = 5 (just like --5 = 5)

    Good idea?
  2. jcsd
  3. Aug 20, 2010 #2


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    People use an exponential notation instead:

    1/5 = 5-1

    (5-1)-1 = 5

    Edit: By the way, you typically have to write -(-5). If you write --5, most people won't know what you're talking about.
  4. Aug 20, 2010 #3


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    Unless you're writing bad C code that is attempting to predecrement a constant:biggrin:
  5. Aug 20, 2010 #4


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    LOL, that thought totally occurred to me as well. :wink:
  6. Aug 20, 2010 #5

    I still think my idea is more consistent with the idea of a negative sign (I code in C quite a bit too, so maybe my inspiration stems from there, since encoding the division sign in a number would be quite elegant in some cases).

    It also means you can have stuff like:

    /5 *10 = 2
    10 /5 = 2 (or maybe 10*/5 = 2, and no that isn't a C comment closing tag).

    So I've swapped the 'numbers' around, and achieved the same result, meaning we have commutativity just like with multiplication. We can even treat *10 = 10 (just like +10 = 10). Has nobody really thought of this crap before?
    Last edited: Aug 20, 2010
  7. Aug 20, 2010 #6


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    I'm pretty content with the way it is at the moment. We already have various ways to represent reciprocals, that being [tex]\frac{1}{x}[/tex] and [tex]x^{-1}[/tex]. As for the minus operator, we don't really have many other ways to express it, so we need at least 1 way to show the negative of a number. We don't need more ways to express what we already have for reciprocals though.

    As for ease of typing, [tex]x^{-1}[/tex] is pretty easy isn't it?

    I wouldn't be surprised if it were implemented in some coding language, but in terms of making it standardized in mathematics, nah dont need it eh
  8. Aug 20, 2010 #7


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    I think it's standard for the arithmetic of a wheel. But there, it's an operation in its own right (a total one, in fact) rather than being an inverse to multiplication or similar kind of thing.
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