Metamath Proof Explorer


Theorem membpartlem19

Description: Together with disjlem19 , this is former prtlem19 . (Contributed by Rodolfo Medina, 15-Oct-2010) (Revised by Mario Carneiro, 12-Aug-2015) (Revised by Peter Mazsa, 21-Oct-2021)

Ref Expression
Assertion membpartlem19 ⊢ B ∈ V → MembPart A → u ∈ A ∧ B ∈ u → u = B ∼ A

Proof

Step Hyp Ref Expression
1 dfmembpart2 ⊢ MembPart A ↔ ElDisj A ∧ ¬ ∅ ∈ A
2 n0el2 ⊢ ¬ ∅ ∈ A ↔ dom ⁡ E -1 ↾ A = A
3 2 biimpi ⊢ ¬ ∅ ∈ A → dom ⁡ E -1 ↾ A = A
4 3 ad2antll ⊢ B ∈ V ∧ ElDisj A ∧ ¬ ∅ ∈ A → dom ⁡ E -1 ↾ A = A
5 4 eleq2d ⊢ B ∈ V ∧ ElDisj A ∧ ¬ ∅ ∈ A → u ∈ dom ⁡ E -1 ↾ A ↔ u ∈ A
6 eldisjlem19 ⊢ B ∈ V → ElDisj A → u ∈ dom ⁡ E -1 ↾ A ∧ B ∈ u → u = B ∼ A
7 6 adantrd ⊢ B ∈ V → ElDisj A ∧ ¬ ∅ ∈ A → u ∈ dom ⁡ E -1 ↾ A ∧ B ∈ u → u = B ∼ A
8 7 imp ⊢ B ∈ V ∧ ElDisj A ∧ ¬ ∅ ∈ A → u ∈ dom ⁡ E -1 ↾ A ∧ B ∈ u → u = B ∼ A
9 8 expd ⊢ B ∈ V ∧ ElDisj A ∧ ¬ ∅ ∈ A → u ∈ dom ⁡ E -1 ↾ A → B ∈ u → u = B ∼ A
10 5 9 sylbird ⊢ B ∈ V ∧ ElDisj A ∧ ¬ ∅ ∈ A → u ∈ A → B ∈ u → u = B ∼ A
11 1 10 sylan2b ⊢ B ∈ V ∧ MembPart A → u ∈ A → B ∈ u → u = B ∼ A
12 11 impd ⊢ B ∈ V ∧ MembPart A → u ∈ A ∧ B ∈ u → u = B ∼ A
13 12 ex ⊢ B ∈ V → MembPart A → u ∈ A ∧ B ∈ u → u = B ∼ A