Metamath Proof Explorer


Theorem lmod1lem5

Description: Lemma 5 for lmod1 . (Contributed by AV, 28-Apr-2019)

Ref Expression
Hypothesis lmod1.m M=BasendxI+ndxIIIScalarndxRndxxBaseR,yIy
Assertion lmod1lem5 IVRRing1ScalarMMI=I

Proof

Step Hyp Ref Expression
1 lmod1.m M=BasendxI+ndxIIIScalarndxRndxxBaseR,yIy
2 fvex BaseRV
3 snex IV
4 2 3 pm3.2i BaseRVIV
5 4 a1i IVRRingBaseRVIV
6 mpoexga BaseRVIVxBaseR,yIyV
7 1 lmodvsca xBaseR,yIyVxBaseR,yIy=M
8 5 6 7 3syl IVRRingxBaseR,yIy=M
9 8 eqcomd IVRRingM=xBaseR,yIy
10 simprr IVRRingx=1ScalarMy=Iy=I
11 1 lmodsca RRingR=ScalarM
12 11 adantl IVRRingR=ScalarM
13 12 eqcomd IVRRingScalarM=R
14 13 fveq2d IVRRing1ScalarM=1R
15 eqid BaseR=BaseR
16 eqid 1R=1R
17 15 16 ringidcl RRing1RBaseR
18 17 adantl IVRRing1RBaseR
19 14 18 eqeltrd IVRRing1ScalarMBaseR
20 snidg IVII
21 20 adantr IVRRingII
22 9 10 19 21 21 ovmpod IVRRing1ScalarMMI=I