Definition
Convex cone.
Lemma 9.1 (Hyperplane separation for cones)
Theorem 9.2 (Farkas’ Lemma)
Corollary 9.3
there exists x s.t. Ax <= b iff.
Corollary 9.4
<c, x> <= \delta iff.
Theorem 9.5 (Duality theorem for linear programming)
Lemma 9.7
When is supremum attained in polyhedron.