If f(x) = 3x^4 - 2x^3 + 5x - 7, what is f'(x)?
Correct answer: A. 12x^3 - 6x^2 + 5
- A. 12x^3 - 6x^2 + 5
- B. 12x^3 - 2x^2 + 5
- C. 3x^3 - 6x^2 + 5
- D. 12x^4 - 6x^3 + 5
Explanation
Apply the power rule to each term: the derivative of 3x^4 is 12x^3, and the derivative of -2x^3 is -6x^2. The constant -7 has derivative zero.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Differentiation and Optimisation
Differentiation covers gradients, standard derivative rules, the product and quotient rules, the chain rule, stationary points and rates of change. Optimisation uses first and second derivatives to classify maxima and minima, while applications include tangent and normal lines, marginal quantities and related rates.
Practise Differentiation and Optimisation
30 free Differentiation and Optimisation MCQs from Quantitative Methods, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Quantitative Methods questions like this
Quantitative Methods is on this paper prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for it.