Theorem csbopabg 4637

Description: Move substitution into a class abstraction. (Contributed by NM, 6-Aug-2007.) (Proof shortened by Mario Carneiro, 17-Nov-2016.)

Assertion

Ref	Expression
csbopabg	|- (A e. V -> [_A / x]_{<.y, z>. | ph} = {<.y, z>. | [.A / x ].ph})

Distinct variable groups:   y,z,A   x,y,z

Allowed substitution hints:   ph(x,y,z)   A(x)   V(x,y,z)

Proof of Theorem csbopabg

Dummy variable w is distinct from all other variables.

Step	Hyp	Ref	Expression
1		csbeq1 3139	. . 3 |- (w = A -> [_w / x]_{<.y, z>. | ph} = [_A / x]_{<.y, z>. | ph})
2		dfsbcq2 3049	. . . 4 |- (w = A -> ([w / x]ph <-> [.A / x ].ph))
3	2	opabbidv 4625	. . 3 |- (w = A -> {<.y, z>. | [w / x]ph} = {<.y, z>. | [.A / x ].ph})
4	1, 3	eqeq12d 2367	. 2 |- (w = A -> ([_w / x]_{<.y, z>. | ph} = {<.y, z>. | [w / x]ph} <-> [_A / x]_{<.y, z>. | ph} = {<.y, z>. | [.A / x ].ph}))
5		vex 2862	. . 3 |- w e. _V
6		nfs1v 2106	. . . 4 |- F/x[w / x]ph
7	6	nfopab 4627	. . 3 |- F/_x{<.y, z>. | [w / x]ph}
8		sbequ12 1919	. . . 4 |- (x = w -> (ph <-> [w / x]ph))
9	8	opabbidv 4625	. . 3 |- (x = w -> {<.y, z>. | ph} = {<.y, z>. | [w / x]ph})
10	5, 7, 9	csbief 3177	. 2 |- [_w / x]_{<.y, z>. | ph} = {<.y, z>. | [w / x]ph}
11	4, 10	vtoclg 2914	1 |- (A e. V -> [_A / x]_{<.y, z>. | ph} = {<.y, z>. | [.A / x ].ph})

Syntax hints:   -> wi 4   = wceq 1642  [wsb 1648   e. wcel 1710   [.wsbc 3046  [_csb 3136  {copab 4622

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334

This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-3an 936  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2478  df-v 2861  df-sbc 3047  df-csb 3137  df-opab 4623

This theorem is referenced by: (None)