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Apparentlyx[SUP]2[/SUP]/y + yis the same

  1. Aug 25, 2011 #1
    apparently

    x2/y + y

    is the same as

    x2+y2/y

    I've done the calculations and it's true. But I can't recall the rule that allows you to do that. It's something about common denominators but I can't remember which.
     
  2. jcsd
  3. Aug 25, 2011 #2
    Re: algebra

    never mind, I got it. if you let x = 4 and y = 3

    then

    4/3 + 3 = 4/3 + 9/3

    and 9/3 = 32/3
     
  4. Aug 25, 2011 #3
    Re: algebra

    Do you mean x2{/SUP]/y + y = x2/y + y2/y? If so, you multiply the expression by 1 = y/y (y not zero).
     
  5. Aug 25, 2011 #4

    HallsofIvy

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    Staff Emeritus
    Science Advisor

    Re: algebra

    No, it is not. But it is the same as (x2+ y2)/y. I assume that is what you meant.

    "which"? There is only one denominator!

    [tex]\frac{x^2}{y}+ y= \frac{x^2}{y}+ \frac{y^2}{y}= \frac{x^2+ y^2}{y}[/tex]
     
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