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Delta/Epsilon Proof for General Cases

  1. Oct 4, 2009 #1
    Hey guys, this isn't a math problem for homework or for a course, but simply for my own interest... This is one that I couldn't crack back in Analysis but that I'd like to get some help on resolving for my own peace of mind:

    Prove f(x,y) = xy is continuous at (x,y) in a domain D[tex]\subset[/tex] R. I can do this easily with specific cases of (x,y) but I couldn't ever figure out the general case :-(
    Last edited: Oct 4, 2009
  2. jcsd
  3. Oct 4, 2009 #2


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    Try writing xy - ab = (xy - ay) + (ay - ab) and working with that.
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