Let K1, le1, K2, le2, a and b be given.
We prove the intermediate
claim Hraw:
(((a,b) 0) 0,((a,b) 1) 0) ∈ le1 ∧ (((a,b) 0) 1,((a,b) 1) 1) ∈ le2.
Apply andI to the current goal.
We prove the intermediate
claim Ha0:
((a,b) 0) 0 = (a 0).
rewrite the current goal using
(tuple_2_0_eq a b) (from left to right).
Use reflexivity.
We prove the intermediate
claim Hb0:
((a,b) 1) 0 = (b 0).
rewrite the current goal using
(tuple_2_1_eq a b) (from left to right).
Use reflexivity.
rewrite the current goal using Ha0 (from right to left).
rewrite the current goal using Hb0 (from right to left).
An
exact proof term for the current goal is
(andEL ((((a,b) 0) 0,((a,b) 1) 0) ∈ le1) ((((a,b) 0) 1,((a,b) 1) 1) ∈ le2) Hraw).
We prove the intermediate
claim Ha1:
((a,b) 0) 1 = (a 1).
rewrite the current goal using
(tuple_2_0_eq a b) (from left to right).
Use reflexivity.
We prove the intermediate
claim Hb1:
((a,b) 1) 1 = (b 1).
rewrite the current goal using
(tuple_2_1_eq a b) (from left to right).
Use reflexivity.
rewrite the current goal using Ha1 (from right to left).
rewrite the current goal using Hb1 (from right to left).
An
exact proof term for the current goal is
(andER ((((a,b) 0) 0,((a,b) 1) 0) ∈ le1) ((((a,b) 0) 1,((a,b) 1) 1) ∈ le2) Hraw).
∎