Theorem cdleme6

Description: Part of proof of Lemma E in Crawley p. 113. This expresses (r \/ f_s(r)) /\ w = u at the top of p. 114. (Contributed by NM, 7-Jun-2012)

	Ref	Expression
Hypotheses	cdleme4.l	⊢ ≤ = ( le ‘ 𝐾 )
	cdleme4.j	⊢ ∨ = ( join ‘ 𝐾 )
	cdleme4.m	⊢ ∧ = ( meet ‘ 𝐾 )
	cdleme4.a	⊢ 𝐴 = ( Atoms ‘ 𝐾 )
	cdleme4.h	⊢ 𝐻 = ( LHyp ‘ 𝐾 )
	cdleme4.u	⊢ 𝑈 = ( ( 𝑃 ∨ 𝑄 ) ∧ 𝑊 )
	cdleme4.f	⊢ 𝐹 = ( ( 𝑆 ∨ 𝑈 ) ∧ ( 𝑄 ∨ ( ( 𝑃 ∨ 𝑆 ) ∧ 𝑊 ) ) )
	cdleme4.g	⊢ 𝐺 = ( ( 𝑃 ∨ 𝑄 ) ∧ ( 𝐹 ∨ ( ( 𝑅 ∨ 𝑆 ) ∧ 𝑊 ) ) )
Assertion	cdleme6	⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ ( 𝑅 ∈ 𝐴 ∧ ¬ 𝑅 ≤ 𝑊 ) ) ∧ ( ( 𝑆 ∈ 𝐴 ∧ ¬ 𝑆 ≤ 𝑊 ) ∧ 𝑅 ≤ ( 𝑃 ∨ 𝑄 ) ) ) → ( ( 𝑅 ∨ 𝐺 ) ∧ 𝑊 ) = 𝑈 )

Proof

Step	Hyp	Ref	Expression
1		cdleme4.l	⊢ ≤ = ( le ‘ 𝐾 )
2		cdleme4.j	⊢ ∨ = ( join ‘ 𝐾 )
3		cdleme4.m	⊢ ∧ = ( meet ‘ 𝐾 )
4		cdleme4.a	⊢ 𝐴 = ( Atoms ‘ 𝐾 )
5		cdleme4.h	⊢ 𝐻 = ( LHyp ‘ 𝐾 )
6		cdleme4.u	⊢ 𝑈 = ( ( 𝑃 ∨ 𝑄 ) ∧ 𝑊 )
7		cdleme4.f	⊢ 𝐹 = ( ( 𝑆 ∨ 𝑈 ) ∧ ( 𝑄 ∨ ( ( 𝑃 ∨ 𝑆 ) ∧ 𝑊 ) ) )
8		cdleme4.g	⊢ 𝐺 = ( ( 𝑃 ∨ 𝑄 ) ∧ ( 𝐹 ∨ ( ( 𝑅 ∨ 𝑆 ) ∧ 𝑊 ) ) )
9	1 2 3 4 5 6 7 8	cdleme5	⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ ( 𝑅 ∈ 𝐴 ∧ ¬ 𝑅 ≤ 𝑊 ) ) ∧ ( ( 𝑆 ∈ 𝐴 ∧ ¬ 𝑆 ≤ 𝑊 ) ∧ 𝑅 ≤ ( 𝑃 ∨ 𝑄 ) ) ) → ( 𝑅 ∨ 𝐺 ) = ( 𝑃 ∨ 𝑄 ) )
10	9	oveq1d	⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ ( 𝑅 ∈ 𝐴 ∧ ¬ 𝑅 ≤ 𝑊 ) ) ∧ ( ( 𝑆 ∈ 𝐴 ∧ ¬ 𝑆 ≤ 𝑊 ) ∧ 𝑅 ≤ ( 𝑃 ∨ 𝑄 ) ) ) → ( ( 𝑅 ∨ 𝐺 ) ∧ 𝑊 ) = ( ( 𝑃 ∨ 𝑄 ) ∧ 𝑊 ) )
11	10 6	eqtr4di	⊢ ( ( ( 𝐾 ∈ HL ∧ 𝑊 ∈ 𝐻 ) ∧ ( 𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ ( 𝑅 ∈ 𝐴 ∧ ¬ 𝑅 ≤ 𝑊 ) ) ∧ ( ( 𝑆 ∈ 𝐴 ∧ ¬ 𝑆 ≤ 𝑊 ) ∧ 𝑅 ≤ ( 𝑃 ∨ 𝑄 ) ) ) → ( ( 𝑅 ∨ 𝐺 ) ∧ 𝑊 ) = 𝑈 )