Function Convex Hull
The convex hull of two or more functions is the largest function that is concave from above and does not exceed the given functions.
See also
Convex Hull, Shapiro's Cyclic Sum ConstantExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Function Convex Hull." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/FunctionConvexHull.html