For f(x) = x⁴ - 4x², which statement about x = 0 is correct?
Correct answer: A. It is a local maximum
- A. It is a local maximum
- B. It is a local minimum
- C. It is a point of inflection
- D. It is not a critical point
Explanation
Here f'(x) = 4x³ - 8x, so x = 0 is a critical point. Since f''(0) = -8, the graph is concave downward there, making x = 0 a local maximum.
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