Metamath Proof Explorer


Theorem pmtrdifellem2

Description: Lemma 2 for pmtrdifel . (Contributed by AV, 15-Jan-2019)

Ref Expression
Hypotheses pmtrdifel.t T=ranpmTrspNK
pmtrdifel.r R=ranpmTrspN
pmtrdifel.0 S=pmTrspNdomQI
Assertion pmtrdifellem2 QTdomSI=domQI

Proof

Step Hyp Ref Expression
1 pmtrdifel.t T=ranpmTrspNK
2 pmtrdifel.r R=ranpmTrspN
3 pmtrdifel.0 S=pmTrspNdomQI
4 3 difeq1i SI=pmTrspNdomQII
5 4 dmeqi domSI=dompmTrspNdomQII
6 eqid pmTrspNK=pmTrspNK
7 6 1 pmtrfb QTNKVQ:NK1-1 ontoNKdomQI2𝑜
8 difsnexi NKVNV
9 f1of Q:NK1-1 ontoNKQ:NKNK
10 fdm Q:NKNKdomQ=NK
11 difssd domQ=NKQIQ
12 dmss QIQdomQIdomQ
13 11 12 syl domQ=NKdomQIdomQ
14 difssd domQ=NKNKN
15 sseq1 domQ=NKdomQNNKN
16 14 15 mpbird domQ=NKdomQN
17 13 16 sstrd domQ=NKdomQIN
18 9 10 17 3syl Q:NK1-1 ontoNKdomQIN
19 id domQI2𝑜domQI2𝑜
20 8 18 19 3anim123i NKVQ:NK1-1 ontoNKdomQI2𝑜NVdomQINdomQI2𝑜
21 7 20 sylbi QTNVdomQINdomQI2𝑜
22 eqid pmTrspN=pmTrspN
23 22 pmtrmvd NVdomQINdomQI2𝑜dompmTrspNdomQII=domQI
24 21 23 syl QTdompmTrspNdomQII=domQI
25 5 24 eqtrid QTdomSI=domQI