Description: In a commutative ring, the product of two ideals is a subset of their intersection. (Contributed by Thierry Arnoux, 17-Jun-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | idlsrgmulrssin.1 | |- S = ( IDLsrg ` R ) |
|
| idlsrgmulrssin.2 | |- B = ( LIdeal ` R ) |
||
| idlsrgmulrssin.3 | |- .(x) = ( .r ` S ) |
||
| idlsrgmulrssin.4 | |- ( ph -> R e. CRing ) |
||
| idlsrgmulrssin.5 | |- ( ph -> I e. B ) |
||
| idlsrgmulrssin.6 | |- ( ph -> J e. B ) |
||
| Assertion | idlsrgmulrssin | |- ( ph -> ( I .(x) J ) C_ ( I i^i J ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | idlsrgmulrssin.1 | |- S = ( IDLsrg ` R ) |
|
| 2 | idlsrgmulrssin.2 | |- B = ( LIdeal ` R ) |
|
| 3 | idlsrgmulrssin.3 | |- .(x) = ( .r ` S ) |
|
| 4 | idlsrgmulrssin.4 | |- ( ph -> R e. CRing ) |
|
| 5 | idlsrgmulrssin.5 | |- ( ph -> I e. B ) |
|
| 6 | idlsrgmulrssin.6 | |- ( ph -> J e. B ) |
|
| 7 | eqid | |- ( .r ` R ) = ( .r ` R ) |
|
| 8 | 1 2 3 7 4 5 6 | idlsrgmulrss1 | |- ( ph -> ( I .(x) J ) C_ I ) |
| 9 | 4 | crngringd | |- ( ph -> R e. Ring ) |
| 10 | 1 2 3 7 9 5 6 | idlsrgmulrss2 | |- ( ph -> ( I .(x) J ) C_ J ) |
| 11 | 8 10 | ssind | |- ( ph -> ( I .(x) J ) C_ ( I i^i J ) ) |