At which critical point does attain a local minimum?

Answer and explanation

Correct answer: D.

  1. Step 1: Differentiate: . Second derivative: . At , , confirming a local minimum. **Answer: . Why not the others:** " local maximum" gives , which corresponds to a local maximum; " inflection point" is where (inflection point), not a local extremum; " exterior point" is not a critical point since .

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