Theorem wwoml3 205

Description: Weak orthomodular law.

Hypotheses

Ref	Expression
wwoml3.1	a =< b
wwoml3.2	(b ^ a_|_) = 0

Assertion

Ref	Expression
wwoml3	(a == b) = 1

Proof of Theorem wwoml3

Step	Hyp	Ref	Expression
1		wwoml3.2	. . . . . 6 (b ^ a_|_) = 0
2	1	ax-r1 34	. . . . 5 0 = (b ^ a_|_)
3		ancom 68	. . . . 5 (b ^ a_|_) = (a_|_ ^ b)
4	2, 3	ax-r2 35	. . . 4 0 = (a_|_ ^ b)
5	4	lor 66	. . 3 (a v 0) = (a v (a_|_ ^ b))
6	5	rbi 90	. 2 ((a v 0) == b) = ((a v (a_|_ ^ b)) == b)
7		or0 94	. . 3 (a v 0) = a
8	7	rbi 90	. 2 ((a v 0) == b) = (a == b)
9		wwoml3.1	. . 3 a =< b
10	9	wwoml2 204	. 2 ((a v (a_|_ ^ b)) == b) = 1
11	6, 8, 10	3tr2 61	1 (a == b) = 1

Syntax hints:   = wb 1   =< wle 2  _|_wn 4   == tb 5   v wo 6   ^ wa 7  1wt 9  0wf 10

This theorem is referenced by:  wwfh1 208  wwfh2 209

This theorem was proved from axioms:  ax-a1 29  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-b 38  df-a 39  df-t 40  df-f 41  df-le2 123

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