Zulip Chat Archive
Stream: new members
Topic: Pushing universal quantifier through and
Felix Kalker (Jul 22 2022 at 12:18):
Hello all, I would like to know if it is possible to prove the following example in one line:
variables (α : Type*) (p q : α → Prop)
example : (∀ x : α, p x ∧ q x) → ∀ y : α, p y :=
begin
intros h y,
exact (h y).left,
end
Thanks for the help!
Johan Commelin (Jul 22 2022 at 12:25):
Does the following count:
variables (α : Type*) (p q : α → Prop)
example : (∀ x : α, p x ∧ q x) → ∀ y : α, p y := assume h y, (h y).left
Johan Commelin (Jul 22 2022 at 12:27):
Or
import tactic
variables (α : Type*) (p q : α → Prop)
example : (∀ x : α, p x ∧ q x) → ∀ y : α, p y := by finish
Andrew Yang (Jul 22 2022 at 12:29):
docs#forall_and_distrib might be useful as well.
Last updated: Dec 20 2023 at 11:08 UTC