English
The Supports predicate is preserved under union: Supports(K1 ∪ K2, S) holds exactly when both Supports(K1,S) and Supports(K2,S) hold.
Русский
Поддержка сохраняется при объединении: Supports(K1 ∪ K2, S) истинен тогда и только тогда, когда выполнены обе условий Supports(K1,S) и Supports(K2,S).
LaTeX
$$$\\mathrm{Supports}(K_1 \\cup K_2, S) \\iff \\mathrm{Supports}(K_1,S) \\land \\mathrm{Supports}(K_2,S).$$$
Lean4
theorem supports_union {K₁ K₂ S} : Supports (K₁ ∪ K₂) S ↔ Supports K₁ S ∧ Supports K₂ S := by
simp [Supports, or_imp, forall_and]