Description: Closure of a finite sum of complex numbers A ( k ) . (Contributed by NM, 9-Nov-2005) (Revised by Mario Carneiro, 22-Apr-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | fsumcl.1 | |- ( ph -> A e. Fin ) |
|
| fsumcl.2 | |- ( ( ph /\ k e. A ) -> B e. CC ) |
||
| Assertion | fsumcl | |- ( ph -> sum_ k e. A B e. CC ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fsumcl.1 | |- ( ph -> A e. Fin ) |
|
| 2 | fsumcl.2 | |- ( ( ph /\ k e. A ) -> B e. CC ) |
|
| 3 | ssidd | |- ( ph -> CC C_ CC ) |
|
| 4 | addcl | |- ( ( x e. CC /\ y e. CC ) -> ( x + y ) e. CC ) |
|
| 5 | 4 | adantl | |- ( ( ph /\ ( x e. CC /\ y e. CC ) ) -> ( x + y ) e. CC ) |
| 6 | 0cnd | |- ( ph -> 0 e. CC ) |
|
| 7 | 3 5 1 2 6 | fsumcllem | |- ( ph -> sum_ k e. A B e. CC ) |