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Homework Help: 2 more pre-cal questions

  1. Aug 10, 2007 #1
    1. The problem statement, all variables and given/known data
    :mad::mad::mad:Find two functions defined implicitly by the relation 9y^2=x^2

    2. Find three ordered pairs in the relation xy=12

    3. The attempt at a solution

    1. my attempt is [tex]f(x)= \sqrt{9y^{2}}[/tex]


    So...is this the right way to do this question?
    am i allowed to put a f() around my x and y and then solve for x and y?

    2. I guess it would be either (2,6) OR (3,4) OR (1,12)
    Is this correct and what the heck is an ordered pair?:surprised
    Last edited by a moderator: Aug 11, 2007
  2. jcsd
  3. Aug 10, 2007 #2


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    Staff: Mentor

    I think you are on the right track. The two relations would be f(x) and f(y), I think. And solving for the ordered pairs (x,y) would be along the lines you suggest.
  4. Aug 10, 2007 #3
    Thanks you!.
  5. Aug 11, 2007 #4


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    Homework Helper

    If 9y^2=x^2 and you solve for y, what do you get?

    y = [tex]\pm\frac{x}{3}[/tex]

    The y is the result of the function... ie f(x), g(x) etc...

    So the two functions implicit here are:

    f(x) = x/3 and g(x) = -x/3
    Last edited: Aug 11, 2007
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