Description: Closure of ring multiplication for a subcomplex module. (Contributed by Mario Carneiro, 16-Oct-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | clm0.f | |- F = ( Scalar ` W ) | |
| clmsub.k | |- K = ( Base ` F ) | ||
| Assertion | clmmcl | |- ( ( W e. CMod /\ X e. K /\ Y e. K ) -> ( X x. Y ) e. K ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | clm0.f | |- F = ( Scalar ` W ) | |
| 2 | clmsub.k | |- K = ( Base ` F ) | |
| 3 | 1 2 | clmsubrg | |- ( W e. CMod -> K e. ( SubRing ` CCfld ) ) | 
| 4 | cnfldmul | |- x. = ( .r ` CCfld ) | |
| 5 | 4 | subrgmcl | |- ( ( K e. ( SubRing ` CCfld ) /\ X e. K /\ Y e. K ) -> ( X x. Y ) e. K ) | 
| 6 | 3 5 | syl3an1 | |- ( ( W e. CMod /\ X e. K /\ Y e. K ) -> ( X x. Y ) e. K ) |