Theorem restfn 17645

Description: The subspace topology operator is a function on pairs. (Contributed by Mario Carneiro, 1-May-2015.)

Assertion

Ref	Expression
restfn	⊢ ↾t Fn (V × V)

Proof of Theorem restfn

Dummy variables 𝑥 𝑗 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-rest 17643	. 2 ⊢ ↾t = (𝑗 ∈ V, 𝑥 ∈ V ↦ ran (𝑦 ∈ 𝑗 ↦ (𝑦 ∩ 𝑥)))
2		vex 3458	. . . 4 ⊢ 𝑗 ∈ V
3	2	mptex 7260	. . 3 ⊢ (𝑦 ∈ 𝑗 ↦ (𝑦 ∩ 𝑥)) ∈ V
4	3	rnex 7956	. 2 ⊢ ran (𝑦 ∈ 𝑗 ↦ (𝑦 ∩ 𝑥)) ∈ V
5	1, 4	fnmpoi 8116	1 ⊢ ↾t Fn (V × V)

This proof depends on syntax axioms:  Vcvv 3454   ∩ cin 4092   ↦ cmpt 5192   × cxp 5656  ran crn 5659   Fn wfn 6561   ↾_t crest 17641

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-rep 5238  ax-sep 5255  ax-nul 5266  ax-pr 5398  ax-un 7783

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-reu 3370  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4841  df-uni 4873  df-iun 4958  df-br 5109  df-opab 5174  df-mpt 5193  df-id 5553  df-xp 5664  df-rel 5665  df-cnv 5666  df-co 5667  df-dm 5668  df-rn 5669  df-res 5670  df-ima 5671  df-iota 6520  df-fun 6568  df-fn 6569  df-f 6570  df-f1 6571  df-fo 6572  df-f1o 6573  df-fv 6574  df-oprab 7455  df-mpo 7456  df-1st 8035  df-2nd 8036  df-rest 17643

This theorem is used by:  0rest  17650  restsspw  17652  firest  17653  restrcl  23530  restbas  23531  ssrest  23549  resstopn  23559