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Use sigma notation to represent the following series for 9 terms.

In which direction does the left side of the graph of this function point? a(x) = 3x - x2 + 4x - 2

Describe the end behavior of the function below. f(x)=(2/3)^x-2 a. as x increases, f(x) approaches infinity. b. as x decreases, f(x) approaches 2. c. as x increases, f(x) approaches -2. d. as x decreases, f(x) approaches negative infinity.