(A) Find a cubic regression equation for the data, and graph it and the data set in the same viewing window.
(B) Use the regression equation and a numerical integration routine on a graphing calculator to approximate (to the nearest dollar) the increased cost in going from a production level of 1 thousand sunglasses per month to 7 thousand sunglasses per month.
Problem
The marginal cost at various levels of output per month for a company that manufactures sunglasses is shown in the following table, with the output x given in thousands of units per month and the total cost C(x) given in thousands of dollars per month:
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(A) Find a quadratic regression equation for the data, and graph it and the data set in the same viewing window.
(B) Use the regression equation and a numerical integration routine on a graphing calculator to approximate (to the nearest dollar) the increased cost in going from a production level of 2 thousand sunglasses per month to 8 thousand sunglasses per month.