Find f'(3) for f(x) = x^3+x^2-4x.
Answer and explanation
Correct answer: C. 29
- Step 1: Differentiate term by term with the power rule: f'(x) = 3x^2+2x-4.
- Step 2: Substitute x = 3: f'(3) = 29.
Answer
29.
Why not the others: '24' is f(3), the function value, not the derivative; '26' forgets to multiply the x^2 term's exponent 2 when differentiating; '33' drops the constant slope term c from the derivative.
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