Metamath Proof Explorer


Theorem lnmlssfg

Description: A submodule of Noetherian module is finitely generated. (Contributed by Stefan O'Rear, 1-Jan-2015)

Ref Expression
Hypotheses lnmlssfg.s
|- S = ( LSubSp ` M )
lnmlssfg.r
|- R = ( M |`s U )
Assertion lnmlssfg
|- ( ( M e. LNoeM /\ U e. S ) -> R e. LFinGen )

Proof

Step Hyp Ref Expression
1 lnmlssfg.s
 |-  S = ( LSubSp ` M )
2 lnmlssfg.r
 |-  R = ( M |`s U )
3 1 islnm
 |-  ( M e. LNoeM <-> ( M e. LMod /\ A. a e. S ( M |`s a ) e. LFinGen ) )
4 3 simprbi
 |-  ( M e. LNoeM -> A. a e. S ( M |`s a ) e. LFinGen )
5 oveq2
 |-  ( a = U -> ( M |`s a ) = ( M |`s U ) )
6 5 2 eqtr4di
 |-  ( a = U -> ( M |`s a ) = R )
7 6 eleq1d
 |-  ( a = U -> ( ( M |`s a ) e. LFinGen <-> R e. LFinGen ) )
8 7 rspcv
 |-  ( U e. S -> ( A. a e. S ( M |`s a ) e. LFinGen -> R e. LFinGen ) )
9 4 8 mpan9
 |-  ( ( M e. LNoeM /\ U e. S ) -> R e. LFinGen )