Theorem relsn 4878

Description: A singleton is a relation iff it is an ordered pair. (Contributed by NM, 24-Sep-2013.)

Hypothesis

Ref	Expression
relsn.1	⊢ 𝐴 ∈ V

Assertion

Ref	Expression
relsn	⊢ (Rel {𝐴} ↔ 𝐴 ∈ (V × V))

Proof of Theorem relsn

Step	Hyp	Ref	Expression
1		df-rel 4779	. 2 ⊢ (Rel {𝐴} ↔ {𝐴} ⊆ (V × V))
2		relsn.1	. . 3 ⊢ 𝐴 ∈ V
3	2	snss 3848	. 2 ⊢ (𝐴 ∈ (V × V) ↔ {𝐴} ⊆ (V × V))
4	1, 3	bitr4i 187	1 ⊢ (Rel {𝐴} ↔ 𝐴 ∈ (V × V))

Syntax hints:   ↔ wb 105   ∈ wcel 2209  Vcvv 2821   ⊆ wss 3220  {csn 3708   × cxp 4770  Rel wrel 4777

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-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-v 2823  df-in 3226  df-ss 3233  df-sn 3714  df-rel 4779

This theorem is referenced by:  relsnop  4879  relsn2m  5256