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Homework Help: Find critical point of interval problem

  1. Oct 7, 2008 #1
    Can you just say that [tex] x(4-x) <4 [/tex] for [tex] x \in (0,2) [/tex]? You don't need to prove this?

    Or to prove this, just find critical point which is [tex] x = 2 [/tex]?
  2. jcsd
  3. Oct 7, 2008 #2


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    Re: interval

    Two ways - you can choose.
    1) Find the places where the left side is zero, pick a value of [tex] x [/tex] from each of the portions of the number line, and check whether the (left side - 4) is positive or negative at each location.
    2) Note that in [tex] (0,2) [/tex] both factors on the left are smaller than two, so...
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