Description: The arbitrary sum of nonnegative extended reals is an extended real. (Contributed by Glauco Siliprandi, 17-Aug-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | sge0xrcl.x | |- ( ph -> X e. V ) |
|
| sge0xrcl.f | |- ( ph -> F : X --> ( 0 [,] +oo ) ) |
||
| Assertion | sge0xrcl | |- ( ph -> ( sum^ ` F ) e. RR* ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | sge0xrcl.x | |- ( ph -> X e. V ) |
|
| 2 | sge0xrcl.f | |- ( ph -> F : X --> ( 0 [,] +oo ) ) |
|
| 3 | iccssxr | |- ( 0 [,] +oo ) C_ RR* |
|
| 4 | 1 2 | sge0cl | |- ( ph -> ( sum^ ` F ) e. ( 0 [,] +oo ) ) |
| 5 | 3 4 | sselid | |- ( ph -> ( sum^ ` F ) e. RR* ) |