Theorem algrflem 6232

Description: Lemma for algrf and related theorems. (Contributed by Mario Carneiro, 28-May-2014.) (Revised by Mario Carneiro, 30-Apr-2015.)

Hypotheses

Ref	Expression
algrflem.1	⊢ 𝐵 ∈ V
algrflem.2	⊢ 𝐶 ∈ V

Assertion

Ref	Expression
algrflem	⊢ (𝐵(𝐹 ∘ 1st )𝐶) = (𝐹‘𝐵)

Proof of Theorem algrflem

Step	Hyp	Ref	Expression
1		df-ov 5880	. 2 ⊢ (𝐵(𝐹 ∘ 1st )𝐶) = ((𝐹 ∘ 1st )‘⟨𝐵, 𝐶⟩)
2		fo1st 6160	. . . 4 ⊢ 1st :V–onto→V
3		fof 5440	. . . 4 ⊢ (1st :V–onto→V → 1st :V⟶V)
4	2, 3	ax-mp 5	. . 3 ⊢ 1st :V⟶V
5		algrflem.1	. . . 4 ⊢ 𝐵 ∈ V
6		algrflem.2	. . . 4 ⊢ 𝐶 ∈ V
7		opexg 4230	. . . 4 ⊢ ((𝐵 ∈ V ∧ 𝐶 ∈ V) → ⟨𝐵, 𝐶⟩ ∈ V)
8	5, 6, 7	mp2an 426	. . 3 ⊢ ⟨𝐵, 𝐶⟩ ∈ V
9		fvco3 5589	. . 3 ⊢ ((1st :V⟶V ∧ ⟨𝐵, 𝐶⟩ ∈ V) → ((𝐹 ∘ 1st )‘⟨𝐵, 𝐶⟩) = (𝐹‘(1st ‘⟨𝐵, 𝐶⟩)))
10	4, 8, 9	mp2an 426	. 2 ⊢ ((𝐹 ∘ 1st )‘⟨𝐵, 𝐶⟩) = (𝐹‘(1st ‘⟨𝐵, 𝐶⟩))
11	5, 6	op1st 6149	. . 3 ⊢ (1st ‘⟨𝐵, 𝐶⟩) = 𝐵
12	11	fveq2i 5520	. 2 ⊢ (𝐹‘(1st ‘⟨𝐵, 𝐶⟩)) = (𝐹‘𝐵)
13	1, 10, 12	3eqtri 2202	1 ⊢ (𝐵(𝐹 ∘ 1st )𝐶) = (𝐹‘𝐵)

Syntax hints:   = wceq 1353   ∈ wcel 2148  Vcvv 2739  ⟨cop 3597   ∘ ccom 4632  ⟶wf 5214  –onto→wfo 5216  ‘cfv 5218  (class class class)co 5877  1^st c1st 6141

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-13 2150  ax-14 2151  ax-ext 2159  ax-sep 4123  ax-pow 4176  ax-pr 4211  ax-un 4435

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ral 2460  df-rex 2461  df-v 2741  df-sbc 2965  df-un 3135  df-in 3137  df-ss 3144  df-pw 3579  df-sn 3600  df-pr 3601  df-op 3603  df-uni 3812  df-br 4006  df-opab 4067  df-mpt 4068  df-id 4295  df-xp 4634  df-rel 4635  df-cnv 4636  df-co 4637  df-dm 4638  df-rn 4639  df-res 4640  df-ima 4641  df-iota 5180  df-fun 5220  df-fn 5221  df-f 5222  df-fo 5224  df-fv 5226  df-ov 5880  df-1st 6143

This theorem is referenced by:  algrf  12047