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6532bunny
If the instructions for a problem ask you to use the smallest possible domain to completely graph two periods of y = 5 + 3 cos 2(x - pi/3), what should be used for Xmin and Xmax? Explain your answer. P.S. "It only wants the first and last numbers for the domain."
You want to have two complete periods. The period of cos is 2 pi. The period of this function is pi, because of the 2 before x. So two periods will fit in the interval [0, 2pi]. If you want the graph to begin with the "normal" starting point of the cos-function, you need to do a bit of extra reasoning: The graph is translated pi/3 to the right, so you also could take as domain: [pi/3, 7pi/3].