Theorem ltlefin 4468

Description: Less than implies less than or equal. (Contributed by SF, 2-Feb-2015.)

Assertion

Ref	Expression
ltlefin	|- ((A e. V /\ B e. W) -> (<<A, B>> e. <fin -> <<A, B>> e. <_fin ))

Proof of Theorem ltlefin

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		addcass 4415	. . . . . . 7 |- ((A +o x) +o 1c) = (A +o (x +o 1c))
2	1	eqeq2i 2363	. . . . . 6 |- (B = ((A +o x) +o 1c) <-> B = (A +o (x +o 1c)))
3		peano2 4403	. . . . . . 7 |- (x e. Nn -> (x +o 1c) e. Nn )
4		addceq2 4384	. . . . . . . . 9 |- (y = (x +o 1c) -> (A +o y) = (A +o (x +o 1c)))
5	4	eqeq2d 2364	. . . . . . . 8 |- (y = (x +o 1c) -> (B = (A +o y) <-> B = (A +o (x +o 1c))))
6	5	rspcev 2955	. . . . . . 7 |- (((x +o 1c) e. Nn /\ B = (A +o (x +o 1c))) -> E.y e. Nn B = (A +o y))
7	3, 6	sylan 457	. . . . . 6 |- ((x e. Nn /\ B = (A +o (x +o 1c))) -> E.y e. Nn B = (A +o y))
8	2, 7	sylan2b 461	. . . . 5 |- ((x e. Nn /\ B = ((A +o x) +o 1c)) -> E.y e. Nn B = (A +o y))
9	8	rexlimiva 2733	. . . 4 |- (E.x e. Nn B = ((A +o x) +o 1c) -> E.y e. Nn B = (A +o y))
10	9	adantl 452	. . 3 |- ((A =/= (/) /\ E.x e. Nn B = ((A +o x) +o 1c)) -> E.y e. Nn B = (A +o y))
11	10	a1i 10	. 2 |- ((A e. V /\ B e. W) -> ((A =/= (/) /\ E.x e. Nn B = ((A +o x) +o 1c)) -> E.y e. Nn B = (A +o y)))
12		opkltfing 4449	. 2 |- ((A e. V /\ B e. W) -> (<<A, B>> e. <fin <-> (A =/= (/) /\ E.x e. Nn B = ((A +o x) +o 1c))))
13		opklefing 4448	. 2 |- ((A e. V /\ B e. W) -> (<<A, B>> e. <_fin <-> E.y e. Nn B = (A +o y)))
14	11, 12, 13	3imtr4d 259	1 |- ((A e. V /\ B e. W) -> (<<A, B>> e. <fin -> <<A, B>> e. <_fin ))

Syntax hints:   -> wi 4   /\ wa 358   = wceq 1642   e. wcel 1710   =/= wne 2516  E.wrex 2615  (/)c0 3550  <<copk 4057  1_cc1c 4134   Nn cnnc 4373   +o cplc 4375   <__fin clefin 4432   <_fin cltfin 4433

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4078  ax-xp 4079  ax-cnv 4080  ax-1c 4081  ax-sset 4082  ax-si 4083  ax-ins2 4084  ax-ins3 4085  ax-typlower 4086  ax-sn 4087

This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-3an 936  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2478  df-ne 2518  df-ral 2619  df-rex 2620  df-v 2861  df-nin 3211  df-compl 3212  df-in 3213  df-un 3214  df-dif 3215  df-symdif 3216  df-ss 3259  df-nul 3551  df-pw 3724  df-sn 3741  df-pr 3742  df-int 3927  df-opk 4058  df-1c 4136  df-pw1 4137  df-xpk 4185  df-cnvk 4186  df-ins2k 4187  df-ins3k 4188  df-imak 4189  df-p6 4191  df-sik 4192  df-ssetk 4193  df-addc 4378  df-nnc 4379  df-lefin 4440  df-ltfin 4441

This theorem is referenced by:  lenltfin  4469