Concept explainers
Polynomial Models Use a graphing calculator to do the following cubic and quartic regression problems. (See Examples 5 and 6.)
Gross National Income The following table shows the gross national income (GNI) in dollars per capita for middle- and upper- income countries for selected years. (Data from: Organization for Economic Cooperation and Development.)
Year | 2000 | 2002 | 2004 | 2006 | 2008 | 2010 | 2012 | 2014 |
GNI | 1768 | 1842 | 2335 | 3148 | 4403 | 5472 | 6949 | 7901 |
a. Plot the data with
b. Use cubic regression to find a third-order polynomial function
c. Graph
d. What does the model predict for the GNI in the year 2017?
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