Convex Cone
A set X is a called a "convex cone" if for any x,y in X and any scalars a>=0 and b>=0, ax+by in X.
See also
Cone, Cone SetExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Convex Cone." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/ConvexCone.html