Theorem u5lemonb 621

Description: Lemma for relevance implication study.

Assertion

Ref	Expression
u5lemonb	((a ->5 b) v b_|_) = (((a ^ b) v (a_|_ ^ b)) v b_|_)

Proof of Theorem u5lemonb

Step	Hyp	Ref	Expression
1		df-i5 47	. . 3 (a ->5 b) = (((a ^ b) v (a_|_ ^ b)) v (a_|_ ^ b_|_))
2	1	ax-r5 37	. 2 ((a ->5 b) v b_|_) = ((((a ^ b) v (a_|_ ^ b)) v (a_|_ ^ b_|_)) v b_|_)
3		ax-a3 31	. . 3 ((((a ^ b) v (a_|_ ^ b)) v (a_|_ ^ b_|_)) v b_|_) = (((a ^ b) v (a_|_ ^ b)) v ((a_|_ ^ b_|_) v b_|_))
4		lear 153	. . . . 5 (a_|_ ^ b_|_) =< b_|_
5	4	df-le2 123	. . . 4 ((a_|_ ^ b_|_) v b_|_) = b_|_
6	5	lor 66	. . 3 (((a ^ b) v (a_|_ ^ b)) v ((a_|_ ^ b_|_) v b_|_)) = (((a ^ b) v (a_|_ ^ b)) v b_|_)
7	3, 6	ax-r2 35	. 2 ((((a ^ b) v (a_|_ ^ b)) v (a_|_ ^ b_|_)) v b_|_) = (((a ^ b) v (a_|_ ^ b)) v b_|_)
8	2, 7	ax-r2 35	1 ((a ->5 b) v b_|_) = (((a ^ b) v (a_|_ ^ b)) v b_|_)

Syntax hints:   = wb 1  _|_wn 4   v wo 6   ^ wa 7   ->5 wi5 17

This theorem is referenced by:  u5lemnab 636  u5lem3 735

This theorem was proved from axioms:  ax-a2 30  ax-a3 31  ax-a5 33  ax-r1 34  ax-r2 35  ax-r4 36  ax-r5 37

This theorem depends on definitions:  df-a 39  df-i5 47  df-le1 122  df-le2 123

metamath.org