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The simple problems always get to me

  1. Aug 3, 2005 #1
    I'm working some problems (pre cal/trig) and I'm surprised at how difficult I keep trying to make everything (trying to prepare for college math and I'm sure I'll figure this out as soon as I post this).

    For some reason these things are eluding me.. I was wondering if anyone could help me, even if this post does make me seem like a total moron.

    (1/x) - (1/y) / (y^2 - x^2)

    That's it. Easy, right? Well for some reason it's bothering the hell out of me. I have an answer sheet, too, I just for the life of me get this problem.

    Thanks for the help tho, you guys rock if you'll help me with this... it'll help prepare me.
     
  2. jcsd
  3. Aug 3, 2005 #2
    Wow... ok the answer is

    1/xy(x+y)

    And I somewhat realize why (tried to work it backwards). My god.... please, feel free to make fun of me now.. or elaborate even more because this place is all about learning eh?
     
  4. Aug 4, 2005 #3

    EnumaElish

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    Always a pleasure. And you're welcome, anytime. :smile:
     
  5. Aug 4, 2005 #4
    [tex] \frac{{x^{ - 1} - y^{ - 1} }}
    {{y^2 - x^2 }} = \frac{{\left( {y - x} \right)\left( {xy} \right)^{ - 1} }}{{\left( {y - x} \right)\left( {y + x} \right)}} = \frac{1}{{xy\left( {y + x} \right)}} [/tex]

    Working backwards may help I suppose. Here is an example (only a mere example!) of a strategy you could use to solve your problem, though it looks funky b/c I refused to put three "fraction/division bars" using LaTex.
     
    Last edited: Aug 4, 2005
  6. Aug 4, 2005 #5
    Thank you so much bomba!
     
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