Theorem riota5 6056

Description: A method for computing restricted iota. (Contributed by NM, 20-Oct-2011.) (Revised by Mario Carneiro, 6-Dec-2016.)

Hypotheses

Ref	Expression
riota5.1	|- ( ph -> B e. A )
riota5.2	|- ( ( ph /\ x e. A ) -> ( ps <-> x = B ) )

Assertion

Ref	Expression
riota5	|- ( ph -> ( iota_ x e. A ps ) = B )

Distinct variable groups:   x, A   x, B   ph, x

Allowed substitution hint:   ps( x)

Proof of Theorem riota5

Step	Hyp	Ref	Expression
1		nfcvd 2393	. 2 |- ( ph -> F/_ x B )
2		riota5.1	. 2 |- ( ph -> B e. A )
3		riota5.2	. 2 |- ( ( ph /\ x e. A ) -> ( ps <-> x = B ) )
4	1, 2, 3	riota5f 6055	1 |- ( ph -> ( iota_ x e. A ps ) = B )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1402   e. wcel 2209   iota_crio 6027

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-reu 2535  df-v 2823  df-sbc 3052  df-un 3224  df-sn 3711  df-pr 3712  df-uni 3931  df-iota 5332  df-riota 6028

This theorem is referenced by:  f1ocnvfv3  6064  caucvgrelemrec  11723  sqrt0  11748  sqrtsq  11788  dfgcd3  12765