is convex if and only if
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2 marksMathematicsConcavity, convexity and quasi-concavityConvex sets and functionsModerateabout 3 min
DSE 2007 Question 41: Concavity, convexity and quasi-concavity
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f:ℜⁿ→ℜ is convex if and only if (A) {(x,r)∈ℜⁿ×ℜ| f(x)≤ r} is convex (B) {(x,r)∈ℜⁿ×ℜ| f(x)≥ r} is convex (C) {x∈ℜⁿ| f(x)≤ r} is convex for every r∈ℜ (D) {x∈ℜⁿ| f(x)≥ r} is convex for every r∈ℜ
Also written as: f: Re^n-> Re is convex if and only if
Concavity, convexity and quasi-concavity has come up 39 times in 6 exams since 2006.
What this question tests
This question is on Convex sets and functions, part of Concavity, convexity and quasi-concavity in Mathematics.
Sets and functions with no dents, and the inequalities that define them.
TestStop has 14 past-paper questions on this subtopic.
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Question from the DSE 2007 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.