Metamath Proof Explorer


Theorem cdlemefr27cl

Description: Part of proof of Lemma E in Crawley p. 113. Closure of N . (Contributed by NM, 23-Mar-2013)

Ref Expression
Hypotheses cdlemefr27.b B = Base K
cdlemefr27.l ˙ = K
cdlemefr27.j ˙ = join K
cdlemefr27.m ˙ = meet K
cdlemefr27.a A = Atoms K
cdlemefr27.h H = LHyp K
cdlemefr27.u U = P ˙ Q ˙ W
cdlemefr27.c C = s ˙ U ˙ Q ˙ P ˙ s ˙ W
cdlemefr27.n N = if s ˙ P ˙ Q I C
Assertion cdlemefr27cl K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q N B

Proof

Step Hyp Ref Expression
1 cdlemefr27.b B = Base K
2 cdlemefr27.l ˙ = K
3 cdlemefr27.j ˙ = join K
4 cdlemefr27.m ˙ = meet K
5 cdlemefr27.a A = Atoms K
6 cdlemefr27.h H = LHyp K
7 cdlemefr27.u U = P ˙ Q ˙ W
8 cdlemefr27.c C = s ˙ U ˙ Q ˙ P ˙ s ˙ W
9 cdlemefr27.n N = if s ˙ P ˙ Q I C
10 simpr2 K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q ¬ s ˙ P ˙ Q
11 10 iffalsed K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q if s ˙ P ˙ Q I C = C
12 9 11 eqtrid K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q N = C
13 simpl1l K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q K HL
14 simpl1r K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q W H
15 simpl2 K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q P A
16 simpl3 K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q Q A
17 simpr1 K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q s A
18 2 3 4 5 6 7 8 1 cdleme1b K HL W H P A Q A s A C B
19 13 14 15 16 17 18 syl23anc K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q C B
20 12 19 eqeltrd K HL W H P A Q A s A ¬ s ˙ P ˙ Q P Q N B