Question: Consider the following data:
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First plot the data, and then try to determine what nonlinear term(s) are needed. If you elect to use trigonometric terms, remember to scale the X values so that they all lie within the interval (0, 2π). Hint: The true model differs slightly from any of the models given in this chapter, but there are other models, with polynomial and/or trigonometric terms, that actually fit the data slightly better than the true model.