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Critical vs stationary point

  1. Oct 11, 2015 #1
    1. The problem statement, all variables and given/known data

    the critical point is the point which the f'(c) = 0 or f'(c) = doesnt exist . How if I'm asked to find the stationary point .

    In this question , the critical point is x=0.071 , -14.071, 3 , and -2

    So, if i am sked to find the stationary point , it should be only x=0.071 , -14.071 , am i right ? x=3 and -2 are excluded ?
    2. Relevant equations

    3. The attempt at a solution

    Attached Files:

  2. jcsd
  3. Oct 11, 2015 #2
    Yes. What do you think about the reason?
  4. Oct 11, 2015 #3

    Ray Vickson

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    Science Advisor
    Homework Helper

    The attachment is incorrect: the function
    [tex] f(x) = \frac{x^2+1}{x^2-x-6} [/tex]
    can be re-written as
    [tex] f(x) = \frac{x^2+1}{(x+2)(x-3)} [/tex]
    Your attachment says that ##f(-2)## and ##f(3)## exist, but that is nonsense: you would be dividing by zero in both cases.

    BTW: please refrain from using such attachments---just type things out. I find that when I open your attachment, I have no way of getting back to PF: I need to log off then log back on again.
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