The real-valued function is
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2 marksMathematicsConcavity, convexity and quasi-concavityTesting concavity and convexityModerateabout 3 min
DSE 2008 Question 52: Concavity, convexity and quasi-concavity
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The real-valued function f(x)=x³ is (A) strictly convex (B) strictly concave (C) neither strictly concave nor strictly convex (D) convex but not strictly convex
Also written as: The real-valued function f(x)=x^3 is
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 2008 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.