The function f(x) = -x^2 + 6x + 1 has its maximum value at x = 3. What is the maximum value?
Answer and explanation
Correct answer: A. 10
- Step 1: f(3) = -9 + 18 + 1 = 10. Answer: 10. Why not the others: 1: That is f(0). 3: That is the position of the maximum, not its value. 28: That treats the x^2 term as positive.
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