Let VVV be a vector space. A subset K⊂VK\subset VK⊂V is convex if for all x,y∈Kx,y \in Kx,y∈K and t∈[0,1]t \in [0,1]t∈[0,1], the vector tx+(1−t)ytx + (1-t)ytx+(1−t)y is in KKK.
Wikidata ID: Q193657