Reputation: 19
I want to prove a goal and I have two hypothesis.
Could you help me in proving the goal? Thank you very much for your help.
Goal : (S m <? S m - (S m - 1)) = true
with two hypothesis
m : nat
H : 1 < 1
H0 : (S m =? 0) = false
Upvotes: 0
Views: 102
Reputation: 29148
1 is not, in fact, less than 1. Therefore, we can prove absurdity. Good thing, too, since the goal itself is otherwise impossible.
Require Import PeanoNat.
contradict H. (* now proving ~(1 < 1) *)
(* Well, < is irreflexive: forall x, ~(x < x). *)
apply Nat.le_irrefl.
Upvotes: 2