Let be the set of real numbers and be a continuous and concave function. Which of the following statements is correct?
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4 marks, −1MathematicsConcavity, convexity and quasi-concavityTesting concavity and convexityModerateabout 2 min
DSE 2018 Question 1: Concavity, convexity and quasi-concavity
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Let ℝ be the set of real numbers and f: ℝ → ℝ be a continuous and concave function. Which of the following statements is correct? (A) |f| must be concave (B) -f must be concave (C) f + f must be concave (D) f ∘ f must be concave
Also written as: Let R be the set of real numbers and f: R -> R be a continuous and concave function. Which of the following statements is correct?
Concavity, convexity and quasi-concavity has come up 39 times in 6 exams since 2006.
What this question tests
This question is on Testing concavity and convexity, part of Concavity, convexity and quasi-concavity in Mathematics.
Checking concavity or convexity from a definition, derivatives or operations that preserve it.
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Question from the DSE 2018 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.