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Homework Help: Calculator Question

  1. Jan 29, 2008 #1
    Cubic Regression

    1. The problem statement, all variables and given/known data
    (I was given a graph to enter into my calculator):

    Let x represent time(in years) since 1980, and let y represent the corresponding U.S production of limousines. Enter the data in a graphing utility and find a cubic regression equation for the data.

    2. Relevant equations
    Calculator steps
    Stat ---> Calc --->CubicReg... now what

    3. The attempt at a solution
    I have found the Cubic Regression equation but have forgotten how to make the equation itself appear in the y equals screen so that I can see the graph. I need that to answer the next part of the question.

    I believe it should look something like this, but I'm not sure exactly how:

    CubicReg L1,Y1,L2

    Any help is greatly appreciated!
    Last edited: Jan 29, 2008
  2. jcsd
  3. Jan 29, 2008 #2
    What kind of calculator do you have?
  4. Jan 29, 2008 #3

    im using a TI-83 Plus
  5. Jan 29, 2008 #4
    I have a TI-89, but this .pdf file may help you out.


    Page 5 tells you how to enter data in list form. In your case, list 1 would be x = years since 1980 = 0, 1, 2, 3, .....
    List 2 would be y variables and the entries would be the number of limousines that correspond to the year in the x column. Ex. In year 1980 (x=0), y = 100000 limousines
    were produced.

    Page 6-7 tell you how to select cubic regression from the STAT menu and enter the lists (L1, L2) that you want to analyze.

    I wish I knew more about the TI-83, but hopefully you can find enough info in the pdf to do the problem.
  6. Jan 29, 2008 #5
    thank you

    thank you very much, I'm sure that will help. I'll go go check it out right now.
  7. Jan 29, 2008 #6
    Thank You

    THANK YOU! You area lifesaver, thank you for taking a little bit of time out of your day to save my whole night!
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