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Homework Help: Absolute extrema

  1. Feb 26, 2008 #1
    {} these brackets are going to represent the absolute value lines
    the problem states
    find the absolute extrema of the given function on each individual interval:
    f(x)= {2x} - {x-2}
    a) [0,1]
    b) [-3, 4]

    I know I need the derivative of the equation but it does not really give a good derivative since it would be f'(x)= 2 - {1}
  2. jcsd
  3. Feb 26, 2008 #2
    well, first what is {2x} equal to when x is from [0,1], als owhat is the value of {x-2}, do the same thing in the other interval!
  4. Feb 26, 2008 #3
    You could also break the function up into the intervals [itex](-\infty,0)[/itex], [itex][0,2)[/itex], and [itex][2,\infty)[/itex] and write f as a piecewise function. Then, you can find the derivative on each of those open intervals (remember that the derivative won't necessarily be defined at 0 and 2).
  5. Feb 26, 2008 #4
    how am i suppose to do tat
  6. Feb 26, 2008 #5
    Do u know how a piecewise defined function looks like? Well, to do that in this case you need to follow both my hints and also PingPong's hints!
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