Theorem ud4lem3b 566

Description: Lemma for unified disjunction.

Assertion

Ref	Expression
ud4lem3b	((a ->4 b)_|_ v (a v b)) = (a v b)

Proof of Theorem ud4lem3b

Step	Hyp	Ref	Expression
1		ud4lem0c 272	. . 3 (a ->4 b)_|_ = (((a_|_ v b_|_) ^ (a v b_|_)) ^ ((a ^ b_|_) v b))
2	1	ax-r5 37	. 2 ((a ->4 b)_|_ v (a v b)) = ((((a_|_ v b_|_) ^ (a v b_|_)) ^ ((a ^ b_|_) v b)) v (a v b))
3		comor1 443	. . . . . . 7 (a v b) C a
4	3	comcom2 175	. . . . . 6 (a v b) C a_|_
5		comor2 444	. . . . . . 7 (a v b) C b
6	5	comcom2 175	. . . . . 6 (a v b) C b_|_
7	4, 6	com2or 465	. . . . 5 (a v b) C (a_|_ v b_|_)
8	3, 6	com2or 465	. . . . 5 (a v b) C (a v b_|_)
9	7, 8	com2an 466	. . . 4 (a v b) C ((a_|_ v b_|_) ^ (a v b_|_))
10	3, 6	com2an 466	. . . . 5 (a v b) C (a ^ b_|_)
11	10, 5	com2or 465	. . . 4 (a v b) C ((a ^ b_|_) v b)
12	9, 11	fh3r 457	. . 3 ((((a_|_ v b_|_) ^ (a v b_|_)) ^ ((a ^ b_|_) v b)) v (a v b)) = ((((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) ^ (((a ^ b_|_) v b) v (a v b)))
13	7, 8	fh3r 457	. . . . . . 7 (((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) = (((a_|_ v b_|_) v (a v b)) ^ ((a v b_|_) v (a v b)))
14		ax-a2 30	. . . . . . . . 9 ((a_|_ v b_|_) v (a v b)) = ((a v b) v (a_|_ v b_|_))
15		or4 77	. . . . . . . . . 10 ((a v b) v (a_|_ v b_|_)) = ((a v a_|_) v (b v b_|_))
16		df-t 40	. . . . . . . . . . . . 13 1 = (b v b_|_)
17	16	lor 66	. . . . . . . . . . . 12 ((a v a_|_) v 1) = ((a v a_|_) v (b v b_|_))
18	17	ax-r1 34	. . . . . . . . . . 11 ((a v a_|_) v (b v b_|_)) = ((a v a_|_) v 1)
19		or1 96	. . . . . . . . . . 11 ((a v a_|_) v 1) = 1
20	18, 19	ax-r2 35	. . . . . . . . . 10 ((a v a_|_) v (b v b_|_)) = 1
21	15, 20	ax-r2 35	. . . . . . . . 9 ((a v b) v (a_|_ v b_|_)) = 1
22	14, 21	ax-r2 35	. . . . . . . 8 ((a_|_ v b_|_) v (a v b)) = 1
23		ax-a2 30	. . . . . . . . 9 ((a v b_|_) v (a v b)) = ((a v b) v (a v b_|_))
24		or4 77	. . . . . . . . . 10 ((a v b) v (a v b_|_)) = ((a v a) v (b v b_|_))
25	16	lor 66	. . . . . . . . . . . 12 ((a v a) v 1) = ((a v a) v (b v b_|_))
26	25	ax-r1 34	. . . . . . . . . . 11 ((a v a) v (b v b_|_)) = ((a v a) v 1)
27		or1 96	. . . . . . . . . . 11 ((a v a) v 1) = 1
28	26, 27	ax-r2 35	. . . . . . . . . 10 ((a v a) v (b v b_|_)) = 1
29	24, 28	ax-r2 35	. . . . . . . . 9 ((a v b) v (a v b_|_)) = 1
30	23, 29	ax-r2 35	. . . . . . . 8 ((a v b_|_) v (a v b)) = 1
31	22, 30	2an 72	. . . . . . 7 (((a_|_ v b_|_) v (a v b)) ^ ((a v b_|_) v (a v b))) = (1 ^ 1)
32	13, 31	ax-r2 35	. . . . . 6 (((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) = (1 ^ 1)
33		an1 98	. . . . . 6 (1 ^ 1) = 1
34	32, 33	ax-r2 35	. . . . 5 (((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) = 1
35		lea 152	. . . . . . 7 (a ^ b_|_) =< a
36	35	leror 144	. . . . . 6 ((a ^ b_|_) v b) =< (a v b)
37	36	df-le2 123	. . . . 5 (((a ^ b_|_) v b) v (a v b)) = (a v b)
38	34, 37	2an 72	. . . 4 ((((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) ^ (((a ^ b_|_) v b) v (a v b))) = (1 ^ (a v b))
39		ancom 68	. . . . 5 (1 ^ (a v b)) = ((a v b) ^ 1)
40		an1 98	. . . . 5 ((a v b) ^ 1) = (a v b)
41	39, 40	ax-r2 35	. . . 4 (1 ^ (a v b)) = (a v b)
42	38, 41	ax-r2 35	. . 3 ((((a_|_ v b_|_) ^ (a v b_|_)) v (a v b)) ^ (((a ^ b_|_) v b) v (a v b))) = (a v b)
43	12, 42	ax-r2 35	. 2 ((((a_|_ v b_|_) ^ (a v b_|_)) ^ ((a ^ b_|_) v b)) v (a v b)) = (a v b)
44	2, 43	ax-r2 35	1 ((a ->4 b)_|_ v (a v b)) = (a v b)

Syntax hints:   = wb 1  _|_wn 4   v wo 6   ^ wa 7  1wt 9   ->4 wi4 16

This theorem is referenced by:  ud4lem3 567

This theorem was proved from axioms:  ax-a1 29  ax-a2 30  ax-a3 31  ax-a4 32  ax-a5 33  ax-r1 34  ax-r2 35  ax-r4 36  ax-r5 37  ax-r3 421

This theorem depends on definitions:  df-b 38  df-a 39  df-t 40  df-f 41  df-i4 46  df-le1 122  df-le2 123  df-c1 124  df-c2 125

metamath.org