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Math Help - Intervals

  1. #1
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    Question Intervals

    For y=(1/4)x^4-(2/3)x^3+(1/2)x^2-3 find the exact intervals on which the function is:

    a) increasing
    b) decreasing
    c) concave up
    d) concave down
    Then find any
    e) local extreme values
    f) inflection points

    I graphed this and came up with the following answers:

    a) (0, infinity)
    b) ( -infinity, 0)
    c) (-infinity, infinity)
    d) none
    e) Min: -3 at x=0
    Max: none
    f) none

    Does that look right?
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  2. #2
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    aren't you supposed to use information from the first and second derivatives to analyze the function, rather than just looking at a graph?
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  3. #3
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    Ok so x^3-2x^2+x would be the first derivative...

    and the second one would be 3x^2-4x+1 ?

    I still don't know how to do it without graphing...but I guess I could graph those two?
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  4. #4
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    have you learned about the first and second derivative tests and what they can tell you about a function?
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