theorem
ENNReal.bdd_le_mul_tendsto_zero
{α : Type u_1}
{l : Filter α}
{f g : α → ENNReal}
{b : ENNReal}
(hb : b ≠ ⊤)
(hf : Filter.Tendsto f l (nhds 0))
(hg : ∀ᶠ (x : α) in l, g x ≤ b)
:
Filter.Tendsto (fun (x : α) => f x * g x) l (nhds 0)
Analogous to bdd_le_mul_tendsto_zero, for ENNReal (which otherwise lacks a continuous
multiplication function). The product of a sequence that tends to zero with any bounded sequence
also tends to zero.
If two functions from finite types have the same multiset of values, there exists a bijection between the domains that commutes with the functions.
theorem
exists_equiv_of_multiset_map_eq
{α : Type u_1}
{β : Type u_2}
{γ : Type u_3}
[Fintype α]
[Fintype β]
[DecidableEq γ]
(f : α → γ)
(g : β → γ)
(h : Multiset.map f Finset.univ.val = Multiset.map g Finset.univ.val)
:
If two functions from finite types have the same multiset of values, there exists a bijection between the domains that commutes with the functions.