Theorem decex 12629

Description: A decimal number is a set. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)

Assertion

Ref	Expression
decex	⊢ ;𝐴𝐵 ∈ V

Proof of Theorem decex

Step	Hyp	Ref	Expression
1		df-dec 12626	. 2 ⊢ ;𝐴𝐵 = (((9 + 1) · 𝐴) + 𝐵)
2	1	ovexi 7403	1 ⊢ ;𝐴𝐵 ∈ V

Syntax hints:   ∈ wcel 2109  Vcvv 3444  (class class class)co 7369  1c1 11045   + caddc 11047   · cmul 11049  9c9 12224  ;cdc 12625

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2701  ax-nul 5256

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-ne 2926  df-v 3446  df-dif 3914  df-un 3916  df-ss 3928  df-nul 4293  df-sn 4586  df-pr 4588  df-uni 4868  df-iota 6452  df-fv 6507  df-ov 7372  df-dec 12626

This theorem is referenced by:  nfermltl2rev  47717