English
If s ⊆ t, then closure(s) ≤ closure(t).
Русский
Если s ⊆ t, то closure(s) ≤ closure(t).
LaTeX
$$$ s \\subseteq t \\Rightarrow \\mathrm{closure}(s) \\le \\mathrm{closure}(t) $$$
Lean4
/-- subsemigroup closure of a set is monotone in its argument: if `s ⊆ t`,
then `closure s ≤ closure t`. -/
@[to_additive (attr := gcongr) /-- Additive subsemigroup closure of a set is monotone in its
argument: if `s ⊆ t`, then `closure s ≤ closure t` -/
]
theorem closure_mono ⦃s t : Set M⦄ (h : s ⊆ t) : closure s ≤ closure t :=
closure_le.2 <| Subset.trans h subset_closure