Let f(x) = 2x^3 + 3x^2 + 4x. What is f'(2)?
Answer and explanation
Correct answer: A. 40
- Step 1: f'(x) = 6x^2 + 6x + 4. Step 2. f'(2) = 6 x 4 + 6 x 2 + 4 = 40. Answer: 40. Why not the others: 36: That is f(x), not the derivative. 34: That differentiates the x^2 term as b x instead of 2b x. 44: That adds the constant c twice.
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