Theorem fodju0 7451

Description: Lemma for fodjuomni 7453 and fodjumkv 7464. A condition which shows that A is empty. (Contributed by Jim Kingdon, 27-Jul-2022.) (Revised by Jim Kingdon, 25-Mar-2023.)

Hypotheses

Ref	Expression
fodjuf.fo	|- ( ph -> F : O -onto-> ( A ⊔ B ) )
fodjuf.p	|- P = ( y e. O |-> if ( E. z e. A ( F ` y ) = (inl ` z ) , (/) , 1o ) )
fodju0.1	|- ( ph -> A. w e. O ( P ` w ) = 1o )

Assertion

Ref	Expression
fodju0	|- ( ph -> A = (/) )

Distinct variable groups:   ph, y, z   y, O, z   z, A   z, B   z, F   y, A   y, F   w, O   w, P

Allowed substitution hints:   ph( w)   A( w)   B( y, w)   P( y, z)   F( w)

Proof of Theorem fodju0

Dummy variables u v are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		fodjuf.fo	. . . . 5 |- ( ph -> F : O -onto-> ( A ⊔ B ) )
2		djulcl 7355	. . . . 5 |- ( u e. A -> (inl ` u ) e. ( A ⊔ B ) )
3		foelrn 5931	. . . . 5 |- ( ( F : O -onto-> ( A ⊔ B ) /\ (inl ` u ) e. ( A ⊔ B ) ) -> E. v e. O (inl ` u ) = ( F ` v ) )
4	1, 2, 3	syl2an 289	. . . 4 |- ( ( ph /\ u e. A ) -> E. v e. O (inl ` u ) = ( F ` v ) )
5		fodjuf.p	. . . . . 6 |- P = ( y e. O |-> if ( E. z e. A ( F ` y ) = (inl ` z ) , (/) , 1o ) )
6		fveqeq2 5684	. . . . . . . 8 |- ( y = v -> ( ( F ` y ) = (inl ` z ) <-> ( F ` v ) = (inl ` z ) ) )
7	6	rexbidv 2545	. . . . . . 7 |- ( y = v -> ( E. z e. A ( F ` y ) = (inl ` z ) <-> E. z e. A ( F ` v ) = (inl ` z ) ) )
8	7	ifbid 3648	. . . . . 6 |- ( y = v -> if ( E. z e. A ( F ` y ) = (inl ` z ) , (/) , 1o ) = if ( E. z e. A ( F ` v ) = (inl ` z ) , (/) , 1o ) )
9		simprl 531	. . . . . 6 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> v e. O )
10		peano1 4721	. . . . . . . 8 |- (/) e. om
11	10	a1i 9	. . . . . . 7 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> (/) e. om )
12		1onn 6766	. . . . . . . 8 |- 1o e. om
13	12	a1i 9	. . . . . . 7 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> 1o e. om )
14	1	fodjuomnilemdc 7448	. . . . . . . 8 |- ( ( ph /\ v e. O ) -> DECID E. z e. A ( F ` v ) = (inl ` z ) )
15	14	ad2ant2r 509	. . . . . . 7 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> DECID E. z e. A ( F ` v ) = (inl ` z ) )
16	11, 13, 15	ifcldcd 3664	. . . . . 6 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> if ( E. z e. A ( F ` v ) = (inl ` z ) , (/) , 1o ) e. om )
17	5, 8, 9, 16	fvmptd3 5776	. . . . 5 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> ( P ` v ) = if ( E. z e. A ( F ` v ) = (inl ` z ) , (/) , 1o ) )
18		fveqeq2 5684	. . . . . 6 |- ( w = v -> ( ( P ` w ) = 1o <-> ( P ` v ) = 1o ) )
19		fodju0.1	. . . . . . 7 |- ( ph -> A. w e. O ( P ` w ) = 1o )
20	19	ad2antrr 488	. . . . . 6 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> A. w e. O ( P ` w ) = 1o )
21	18, 20, 9	rspcdva 2928	. . . . 5 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> ( P ` v ) = 1o )
22		simplr 529	. . . . . . 7 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> u e. A )
23		simprr 533	. . . . . . . 8 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> (inl ` u ) = ( F ` v ) )
24	23	eqcomd 2240	. . . . . . 7 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> ( F ` v ) = (inl ` u ) )
25		fveq2 5675	. . . . . . . 8 |- ( z = u -> (inl ` z ) = (inl ` u ) )
26	25	rspceeqv 2942	. . . . . . 7 |- ( ( u e. A /\ ( F ` v ) = (inl ` u ) ) -> E. z e. A ( F ` v ) = (inl ` z ) )
27	22, 24, 26	syl2anc 411	. . . . . 6 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> E. z e. A ( F ` v ) = (inl ` z ) )
28	27	iftrued 3633	. . . . 5 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> if ( E. z e. A ( F ` v ) = (inl ` z ) , (/) , 1o ) = (/) )
29	17, 21, 28	3eqtr3rd 2276	. . . 4 |- ( ( ( ph /\ u e. A ) /\ ( v e. O /\ (inl ` u ) = ( F ` v ) ) ) -> (/) = 1o )
30	4, 29	rexlimddv 2667	. . 3 |- ( ( ph /\ u e. A ) -> (/) = 1o )
31		1n0 6678	. . . . 5 |- 1o =/= (/)
32	31	nesymi 2460	. . . 4 |- -. (/) = 1o
33	32	a1i 9	. . 3 |- ( ( ph /\ u e. A ) -> -. (/) = 1o )
34	30, 33	pm2.65da 667	. 2 |- ( ph -> -. u e. A )
35	34	eq0rdv 3557	1 |- ( ph -> A = (/) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104  DECID wdc 842   = wceq 1398   e. wcel 2205   A.wral 2522   E.wrex 2523   (/)c0 3512   ifcif 3624   |-> cmpt 4176   omcom 4717   -onto->wfo 5355   ` cfv 5357   1oc1o 6653   ⊔ cdju 7341  inlcinl 7349

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4233  ax-nul 4241  ax-pow 4292  ax-pr 4327  ax-un 4559

This theorem depends on definitions:  df-bi 117  df-dc 843  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-ral 2527  df-rex 2528  df-v 2817  df-sbc 3046  df-csb 3142  df-dif 3216  df-un 3218  df-in 3220  df-ss 3227  df-nul 3513  df-if 3625  df-pw 3676  df-sn 3700  df-pr 3701  df-op 3703  df-uni 3920  df-int 3955  df-br 4115  df-opab 4177  df-mpt 4178  df-tr 4214  df-id 4419  df-iord 4492  df-on 4494  df-suc 4497  df-iom 4718  df-xp 4760  df-rel 4761  df-cnv 4762  df-co 4763  df-dm 4764  df-rn 4765  df-res 4766  df-ima 4767  df-iota 5317  df-fun 5359  df-fn 5360  df-f 5361  df-f1 5362  df-fo 5363  df-f1o 5364  df-fv 5365  df-1st 6347  df-2nd 6348  df-1o 6660  df-dju 7342  df-inl 7351  df-inr 7352

This theorem is referenced by:  fodjuomnilemres  7452  fodjumkvlemres  7463