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* ) |