Metamath Proof Explorer


Theorem cvrntr

Description: The covers relation is not transitive. ( cvntr analog.) (Contributed by NM, 18-Jun-2012)

Ref Expression
Hypotheses cvrntr.b ⊢ B = Base K
cvrntr.c ⊢ C = ⋖ K
Assertion cvrntr ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B ∧ Z ∈ B → X C Y ∧ Y C Z → ¬ X C Z

Proof

Step Hyp Ref Expression
1 cvrntr.b ⊢ B = Base K
2 cvrntr.c ⊢ C = ⋖ K
3 eqid ⊢ < K = < K
4 1 3 2 cvrlt ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B ∧ X C Y → X < K Y
5 4 ex ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B → X C Y → X < K Y
6 5 3adant3r3 ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B ∧ Z ∈ B → X C Y → X < K Y
7 1 3 2 ltcvrntr ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B ∧ Z ∈ B → X < K Y ∧ Y C Z → ¬ X C Z
8 6 7 syland ⊢ K ∈ A ∧ X ∈ B ∧ Y ∈ B ∧ Z ∈ B → X C Y ∧ Y C Z → ¬ X C Z