Let f(x) = 4x^3 + 2x^2 + 3x. What is f'(1)?
Answer and explanation
Correct answer: A. 19
- Step 1: f'(x) = 12x^2 + 4x + 3. Step 2. f'(1) = 12 x 1 + 4 x 1 + 3 = 19. Answer: 19. Why not the others: 9: That is f(x), not the derivative. 17: That differentiates the x^2 term as b x instead of 2b x. 22: That adds the constant c twice.
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