Theorem mpteq1df 41512

Description: An equality theorem for the maps-to notation. (Contributed by Glauco Siliprandi, 23-Oct-2021.)

Hypotheses

Ref	Expression
mpteq1df.1	⊢ Ⅎ𝑥𝜑
mpteq1df.2	⊢ (𝜑 → 𝐴 = 𝐵)

Assertion

Ref	Expression
mpteq1df	⊢ (𝜑 → (𝑥 ∈ 𝐴 ↦ 𝐶) = (𝑥 ∈ 𝐵 ↦ 𝐶))

Proof of Theorem mpteq1df

Step	Hyp	Ref	Expression
1		mpteq1df.1	. . 3 ⊢ Ⅎ𝑥𝜑
2		mpteq1df.2	. . 3 ⊢ (𝜑 → 𝐴 = 𝐵)
3	1, 2	alrimi 2212	. 2 ⊢ (𝜑 → ∀𝑥 𝐴 = 𝐵)
4		eqid 2824	. . 3 ⊢ 𝐶 = 𝐶
5	4	rgenw 3153	. 2 ⊢ ∀𝑥 ∈ 𝐴 𝐶 = 𝐶
6		mpteq12f 5152	. 2 ⊢ ((∀𝑥 𝐴 = 𝐵 ∧ ∀𝑥 ∈ 𝐴 𝐶 = 𝐶) → (𝑥 ∈ 𝐴 ↦ 𝐶) = (𝑥 ∈ 𝐵 ↦ 𝐶))
7	3, 5, 6	sylancl 588	1 ⊢ (𝜑 → (𝑥 ∈ 𝐴 ↦ 𝐶) = (𝑥 ∈ 𝐵 ↦ 𝐶))

Syntax hints:   → wi 4  ∀wal 1534   = wceq 1536  Ⅎwnf 1783  ∀wral 3141   ↦ cmpt 5149

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 1969  ax-7 2014  ax-8 2115  ax-9 2123  ax-10 2144  ax-12 2176  ax-ext 2796

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-tru 1539  df-ex 1780  df-nf 1784  df-sb 2069  df-clab 2803  df-cleq 2817  df-clel 2896  df-ral 3146  df-opab 5132  df-mpt 5150

This theorem is referenced by:  smfliminflem  43111