Theorem fvmptnf 6526

Description: The value of a function given by an ordered-pair class abstraction is the empty set when the class it would otherwise map to is a proper class. This version of fvmptn 6527 uses bound-variable hypotheses instead of distinct variable conditions. (Contributed by NM, 21-Oct-2003.) (Revised by Mario Carneiro, 11-Sep-2015.)

Hypotheses

Ref	Expression
fvmptf.1	⊢ Ⅎ𝑥𝐴
fvmptf.2	⊢ Ⅎ𝑥𝐶
fvmptf.3	⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
fvmptf.4	⊢ 𝐹 = (𝑥 ∈ 𝐷 ↦ 𝐵)

Assertion

Ref	Expression
fvmptnf	⊢ (¬ 𝐶 ∈ V → (𝐹‘𝐴) = ∅)

Distinct variable group:   𝑥,𝐷

Allowed substitution hints:   𝐴(𝑥)   𝐵(𝑥)   𝐶(𝑥)   𝐹(𝑥)

Proof of Theorem fvmptnf

Step	Hyp	Ref	Expression
1		fvmptf.4	. . . . 5 ⊢ 𝐹 = (𝑥 ∈ 𝐷 ↦ 𝐵)
2	1	dmmptss 5852	. . . 4 ⊢ dom 𝐹 ⊆ 𝐷
3	2	sseli 3801	. . 3 ⊢ (𝐴 ∈ dom 𝐹 → 𝐴 ∈ 𝐷)
4		eqid 2813	. . . . . . 7 ⊢ (𝑥 ∈ 𝐷 ↦ ( I ‘𝐵)) = (𝑥 ∈ 𝐷 ↦ ( I ‘𝐵))
5	1, 4	fvmptex 6518	. . . . . 6 ⊢ (𝐹‘𝐴) = ((𝑥 ∈ 𝐷 ↦ ( I ‘𝐵))‘𝐴)
6		fvex 6424	. . . . . . 7 ⊢ ( I ‘𝐶) ∈ V
7		fvmptf.1	. . . . . . . 8 ⊢ Ⅎ𝑥𝐴
8		nfcv 2955	. . . . . . . . 9 ⊢ Ⅎ𝑥 I
9		fvmptf.2	. . . . . . . . 9 ⊢ Ⅎ𝑥𝐶
10	8, 9	nffv 6421	. . . . . . . 8 ⊢ Ⅎ𝑥( I ‘𝐶)
11		fvmptf.3	. . . . . . . . 9 ⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
12	11	fveq2d 6415	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → ( I ‘𝐵) = ( I ‘𝐶))
13	7, 10, 12, 4	fvmptf 6525	. . . . . . 7 ⊢ ((𝐴 ∈ 𝐷 ∧ ( I ‘𝐶) ∈ V) → ((𝑥 ∈ 𝐷 ↦ ( I ‘𝐵))‘𝐴) = ( I ‘𝐶))
14	6, 13	mpan2 674	. . . . . 6 ⊢ (𝐴 ∈ 𝐷 → ((𝑥 ∈ 𝐷 ↦ ( I ‘𝐵))‘𝐴) = ( I ‘𝐶))
15	5, 14	syl5eq 2859	. . . . 5 ⊢ (𝐴 ∈ 𝐷 → (𝐹‘𝐴) = ( I ‘𝐶))
16		fvprc 6404	. . . . 5 ⊢ (¬ 𝐶 ∈ V → ( I ‘𝐶) = ∅)
17	15, 16	sylan9eq 2867	. . . 4 ⊢ ((𝐴 ∈ 𝐷 ∧ ¬ 𝐶 ∈ V) → (𝐹‘𝐴) = ∅)
18	17	expcom 400	. . 3 ⊢ (¬ 𝐶 ∈ V → (𝐴 ∈ 𝐷 → (𝐹‘𝐴) = ∅))
19	3, 18	syl5 34	. 2 ⊢ (¬ 𝐶 ∈ V → (𝐴 ∈ dom 𝐹 → (𝐹‘𝐴) = ∅))
20		ndmfv 6441	. 2 ⊢ (¬ 𝐴 ∈ dom 𝐹 → (𝐹‘𝐴) = ∅)
21	19, 20	pm2.61d1 172	1 ⊢ (¬ 𝐶 ∈ V → (𝐹‘𝐴) = ∅)

Syntax hints:  ¬ wn 3   → wi 4   = wceq 1637   ∈ wcel 2157  Ⅎwnfc 2942  Vcvv 3398  ∅c0 4123   ↦ cmpt 4930   I cid 5225  dom cdm 5318  ‘cfv 6104

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1877  ax-4 1894  ax-5 2001  ax-6 2069  ax-7 2105  ax-8 2159  ax-9 2166  ax-10 2186  ax-11 2202  ax-12 2215  ax-13 2422  ax-ext 2791  ax-sep 4982  ax-nul 4990  ax-pow 5042  ax-pr 5103

This theorem depends on definitions:  df-bi 198  df-an 385  df-or 866  df-3an 1102  df-tru 1641  df-ex 1860  df-nf 1864  df-sb 2062  df-mo 2635  df-eu 2638  df-clab 2800  df-cleq 2806  df-clel 2809  df-nfc 2944  df-ral 3108  df-rex 3109  df-rab 3112  df-v 3400  df-sbc 3641  df-csb 3736  df-dif 3779  df-un 3781  df-in 3783  df-ss 3790  df-nul 4124  df-if 4287  df-sn 4378  df-pr 4380  df-op 4384  df-uni 4638  df-br 4852  df-opab 4914  df-mpt 4931  df-id 5226  df-xp 5324  df-rel 5325  df-cnv 5326  df-co 5327  df-dm 5328  df-rn 5329  df-res 5330  df-ima 5331  df-iota 6067  df-fun 6106  df-fn 6107  df-fv 6112

This theorem is referenced by:  fvmptn  6527  rdgsucmptnf  7764  frsucmptn  7773