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Two basic geometry questions

  1. May 5, 2008 #1
    If a triangle has two legs with lengths of 2 each, is the maximum permiter of that triangle 8, or 7.999 (repeating)? In other words, is the maximum angle of a triangle 180 degrees, or 17.999 (repeating) degrees?

    Also, if a rectangle has two opposite sides with lengths of 2, is the minimum permiter of that rectangle 4, or 4.000000....1 (approching 4)?

    Thank you!
  2. jcsd
  3. May 5, 2008 #2
    Mathematically its not too hard to prove (using infinite an series) that 7.9999... (on indefinitely) is the same as 8. Similarly for 4.00000...
  4. May 5, 2008 #3
    In the first case, there is no maximum perimeter; however, 8 is the least upper bound of the possible perimiters of the triangle.

    The second case is similar: no minimum perimeter.
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