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Homework Help: Quick Questions: Need Checking

  1. May 17, 2012 #1
    https://www.physicsforums.com/attachment.php?attachmentid=47375&stc=1&d=1337282982
    Given the following graph of the function y = ƒ(x) Find the interval(s) x value(s) for which each of the following is/are true ( Enter your answers separated by commas with no spaces. eg. A

    ƒ′(x) = 0

    = B, C

    ƒ′(x) > 0

    = D

    ƒ′(x) < 0

    = A


    The displacement of an object is given by the equation s(t) = 2t^2 + 5 then at time:
    a. t = 2 the velocity is = 13
    b. t = 5 the velocity is = 55
    c. t = 2.5 the velocity is = 18


    For the function ƒ(x) = x^3 - 4x, what is the average rate of change between:
    a. x = 3 and x = 4? = 33
    b. x = 0 and x = 0.5? = -3.75

    What is the simplified average rate of change between x = 2 and x = 2 + h for the function:
    (Enter your expression as you would enter an equation in Winplot)
    a. ƒ(x) = x2? = 4+h
    b. ƒ(x) = 1/x? = -1/4+2h

    For the function ƒ(x) = 2x^2 + 5, calculate f(a+h)-f(a)/h
    a. x = 5
    = 55
    b. x = 0.1
    = 5.02
     

    Attached Files:

  2. jcsd
  3. May 17, 2012 #2
    Graph question: two wrong.
    Displacement & velocity - all those are wrong.
    Average rate of change - both right.
    (2+h) - wrong as written, but I suspect you actually have these right with better use of brackets and symbols.
    f(a+h) etc - both wrong, also missing brackets in question.
     
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