Theorem mpteq2i 3947

Description: An equality inference for the maps-to notation. (Contributed by Mario Carneiro, 16-Dec-2013.)

Hypothesis

Ref	Expression
mpteq2i.1	⊢ 𝐵 = 𝐶

Assertion

Ref	Expression
mpteq2i	⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑥 ∈ 𝐴 ↦ 𝐶)

Proof of Theorem mpteq2i

Step	Hyp	Ref	Expression
1		mpteq2i.1	. . 3 ⊢ 𝐵 = 𝐶
2	1	a1i 9	. 2 ⊢ (𝑥 ∈ 𝐴 → 𝐵 = 𝐶)
3	2	mpteq2ia 3946	1 ⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑥 ∈ 𝐴 ↦ 𝐶)

Syntax hints:   = wceq 1296   ∈ wcel 1445   ↦ cmpt 3921

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1388  ax-7 1389  ax-gen 1390  ax-ie1 1434  ax-ie2 1435  ax-8 1447  ax-11 1449  ax-4 1452  ax-17 1471  ax-i9 1475  ax-ial 1479  ax-i5r 1480  ax-ext 2077

This theorem depends on definitions:  df-bi 116  df-tru 1299  df-nf 1402  df-sb 1700  df-clab 2082  df-cleq 2088  df-clel 2091  df-ral 2375  df-opab 3922  df-mpt 3923

This theorem is referenced by:  frecsuc  6210  fodjuomni  6892  fodjumkv  6903  axcaucvg  7532  0tonninf  9994  1tonninf  9995  cbvsum  10903  eirraplem  11213  nninfsellemqall  12621  nninfomni  12625  exmidsbthr  12627