Description: The generalized sum of nonnegative extended reals is an extended real. (Contributed by Glauco Siliprandi, 11-Oct-2020)
Ref | Expression | ||
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Hypotheses | sge0xrclmpt.xph | |- F/ x ph |
|
sge0xrclmpt.a | |- ( ph -> A e. V ) |
||
sge0xrclmpt.b | |- ( ( ph /\ x e. A ) -> B e. ( 0 [,] +oo ) ) |
||
Assertion | sge0xrclmpt | |- ( ph -> ( sum^ ` ( x e. A |-> B ) ) e. RR* ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sge0xrclmpt.xph | |- F/ x ph |
|
2 | sge0xrclmpt.a | |- ( ph -> A e. V ) |
|
3 | sge0xrclmpt.b | |- ( ( ph /\ x e. A ) -> B e. ( 0 [,] +oo ) ) |
|
4 | iccssxr | |- ( 0 [,] +oo ) C_ RR* |
|
5 | 1 2 3 | sge0clmpt | |- ( ph -> ( sum^ ` ( x e. A |-> B ) ) e. ( 0 [,] +oo ) ) |
6 | 4 5 | sselid | |- ( ph -> ( sum^ ` ( x e. A |-> B ) ) e. RR* ) |