For the exponential function f, the table above shows several values of x and their corresponding values of , where a is a constant greater than 1. If k is a constant and , what is the value of k ?
Correct answer: 8
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Explanation
The correct answer is 8. The values of for the exponential function f shown in the table increase by a factor of for each increase of 1 in x. This relationship can be represented by the equation , where b is a constant. It’s given that when , . Substituting 2 for x and for into yields . Since , it follows that . Thus, an equation that defines the function f is . It follows that the value of k such that can be found by solving the equation , which yields .
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id cb_question_bank:ea166a5e-c813-4109-85fa-700fdc50edf9 · question 43926bd9 · IBN 029650-DC
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