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Homework Help: Bounded Region

  1. Jun 20, 2007 #1
    1. The problem statement, all variables and given/known data
    Ok I just wanted to make sure of this one.
    Write inequalities to describe the region:
    The solid rectangular box in the first octant bounded by the pane x=1 y=2 z=3.

    3. The attempt at a solution
    I thought of it as the volume of the box bounded boy the planes so:
    [tex]0\leq xyz\leq 6[/tex]
     
  2. jcsd
  3. Jun 20, 2007 #2

    Hurkyl

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    So, you are claiming that the point
    (1000, -1/100, -1/10)​
    lies in the box?
     
  4. Jun 20, 2007 #3
    ok so how about

    [tex]0\leq x+y+z \leq 6[/tex]
     
  5. Jun 20, 2007 #4

    Hurkyl

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    What about the point (100, 200, -300)?

    (Oh, and why do you think (1000, -1/100, -1/10) isn't in the box?)
     
  6. Jun 20, 2007 #5
    They are all in the box. Should I just make a contraint for each varible?
     
  7. Jun 20, 2007 #6

    Hurkyl

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    That's certainly a reasonable thing to do.
     
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