Theorem ids1 14040

Description: Identity function protection for a singleton word. (Contributed by Mario Carneiro, 26-Feb-2016.)

Assertion

Ref	Expression
ids1	⊢ ⟨“𝐴”⟩ = ⟨“( I ‘𝐴)”⟩

Proof of Theorem ids1

Step	Hyp	Ref	Expression
1		fvex 6687	. . . . 5 ⊢ ( I ‘𝐴) ∈ V
2		fvi 6744	. . . . 5 ⊢ (( I ‘𝐴) ∈ V → ( I ‘( I ‘𝐴)) = ( I ‘𝐴))
3	1, 2	ax-mp 5	. . . 4 ⊢ ( I ‘( I ‘𝐴)) = ( I ‘𝐴)
4	3	opeq2i 4765	. . 3 ⊢ ⟨0, ( I ‘( I ‘𝐴))⟩ = ⟨0, ( I ‘𝐴)⟩
5	4	sneqi 4527	. 2 ⊢ {⟨0, ( I ‘( I ‘𝐴))⟩} = {⟨0, ( I ‘𝐴)⟩}
6		df-s1 14039	. 2 ⊢ ⟨“( I ‘𝐴)”⟩ = {⟨0, ( I ‘( I ‘𝐴))⟩}
7		df-s1 14039	. 2 ⊢ ⟨“𝐴”⟩ = {⟨0, ( I ‘𝐴)⟩}
8	5, 6, 7	3eqtr4ri 2772	1 ⊢ ⟨“𝐴”⟩ = ⟨“( I ‘𝐴)”⟩

Syntax hints:   = wceq 1542   ∈ wcel 2114  Vcvv 3398  {csn 4516  ⟨cop 4522   I cid 5428  ‘cfv 6339  0cc0 10615  ⟨“cs1 14038

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1917  ax-6 1975  ax-7 2020  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2162  ax-12 2179  ax-ext 2710  ax-sep 5167  ax-nul 5174  ax-pr 5296

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 847  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1787  df-nf 1791  df-sb 2075  df-mo 2540  df-eu 2570  df-clab 2717  df-cleq 2730  df-clel 2811  df-nfc 2881  df-ral 3058  df-rex 3059  df-v 3400  df-sbc 3681  df-dif 3846  df-un 3848  df-in 3850  df-ss 3860  df-nul 4212  df-if 4415  df-sn 4517  df-pr 4519  df-op 4523  df-uni 4797  df-br 5031  df-opab 5093  df-id 5429  df-xp 5531  df-rel 5532  df-cnv 5533  df-co 5534  df-dm 5535  df-iota 6297  df-fun 6341  df-fv 6347  df-s1 14039

This theorem is referenced by:  s1prc  14047  s1cli  14048  revs1  14216