Theorem mpteq12i 4016

Description: An equality inference for the maps-to notation. (Contributed by Scott Fenton, 27-Oct-2010.) (Revised by Mario Carneiro, 16-Dec-2013.)

Hypotheses

Ref	Expression
mpteq12i.1	⊢ 𝐴 = 𝐶
mpteq12i.2	⊢ 𝐵 = 𝐷

Assertion

Ref	Expression
mpteq12i	⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑥 ∈ 𝐶 ↦ 𝐷)

Proof of Theorem mpteq12i

Step	Hyp	Ref	Expression
1		mpteq12i.1	. . . 4 ⊢ 𝐴 = 𝐶
2	1	a1i 9	. . 3 ⊢ (⊤ → 𝐴 = 𝐶)
3		mpteq12i.2	. . . 4 ⊢ 𝐵 = 𝐷
4	3	a1i 9	. . 3 ⊢ (⊤ → 𝐵 = 𝐷)
5	2, 4	mpteq12dv 4010	. 2 ⊢ (⊤ → (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑥 ∈ 𝐶 ↦ 𝐷))
6	5	mptru 1340	1 ⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑥 ∈ 𝐶 ↦ 𝐷)

Syntax hints:   = wceq 1331  ⊤wtru 1332   ↦ cmpt 3989

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-11 1484  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121

This theorem depends on definitions:  df-bi 116  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2126  df-cleq 2132  df-clel 2135  df-ral 2421  df-opab 3990  df-mpt 3991

This theorem is referenced by:  offres  6033