Metamath Proof Explorer


Theorem lmod1lem1

Description: Lemma 1 for lmod1 . (Contributed by AV, 28-Apr-2019)

Ref Expression
Hypothesis lmod1.m M=BasendxI+ndxIIIScalarndxRndxxBaseR,yIy
Assertion lmod1lem1 IVRRingrBaseRrMII

Proof

Step Hyp Ref Expression
1 lmod1.m M=BasendxI+ndxIIIScalarndxRndxxBaseR,yIy
2 fvex BaseRV
3 snex IV
4 3 a1i IVRRingrBaseRIV
5 mpoexga BaseRVIVxBaseR,yIyV
6 2 4 5 sylancr IVRRingrBaseRxBaseR,yIyV
7 1 lmodvsca xBaseR,yIyVxBaseR,yIy=M
8 6 7 syl IVRRingrBaseRxBaseR,yIy=M
9 8 eqcomd IVRRingrBaseRM=xBaseR,yIy
10 simprr IVRRingrBaseRx=ry=Iy=I
11 simp3 IVRRingrBaseRrBaseR
12 snidg IVII
13 12 3ad2ant1 IVRRingrBaseRII
14 9 10 11 13 13 ovmpod IVRRingrBaseRrMI=I
15 14 13 eqeltrd IVRRingrBaseRrMII