Description: The arbitrary sum of nonnegative extended reals is an extended real. (Contributed by Glauco Siliprandi, 17-Aug-2020)
Ref | Expression | ||
---|---|---|---|
Hypotheses | sge0xrcl.x | ⊢ ( 𝜑 → 𝑋 ∈ 𝑉 ) | |
sge0xrcl.f | ⊢ ( 𝜑 → 𝐹 : 𝑋 ⟶ ( 0 [,] +∞ ) ) | ||
Assertion | sge0xrcl | ⊢ ( 𝜑 → ( Σ^ ‘ 𝐹 ) ∈ ℝ* ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sge0xrcl.x | ⊢ ( 𝜑 → 𝑋 ∈ 𝑉 ) | |
2 | sge0xrcl.f | ⊢ ( 𝜑 → 𝐹 : 𝑋 ⟶ ( 0 [,] +∞ ) ) | |
3 | iccssxr | ⊢ ( 0 [,] +∞ ) ⊆ ℝ* | |
4 | 1 2 | sge0cl | ⊢ ( 𝜑 → ( Σ^ ‘ 𝐹 ) ∈ ( 0 [,] +∞ ) ) |
5 | 3 4 | sselid | ⊢ ( 𝜑 → ( Σ^ ‘ 𝐹 ) ∈ ℝ* ) |