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Theorem climmul 14740
 Description: Limit of the product of two converging sequences. Proposition 12-2.1(c) of [Gleason] p. 168. (Contributed by NM, 27-Dec-2005.) (Proof shortened by Mario Carneiro, 1-Feb-2014.)
Hypotheses
Ref Expression
climadd.8 ((𝜑𝑘𝑍) → (𝐹𝑘) ∈ ℂ)
climadd.9 ((𝜑𝑘𝑍) → (𝐺𝑘) ∈ ℂ)
climmul.h ((𝜑𝑘𝑍) → (𝐻𝑘) = ((𝐹𝑘) · (𝐺𝑘)))
Assertion
Ref Expression
climmul (𝜑𝐻 ⇝ (𝐴 · 𝐵))
Distinct variable groups:   𝐵,𝑘   𝑘,𝐹   𝜑,𝑘   𝐴,𝑘   𝑘,𝐺   𝑘,𝐻   𝑘,𝑀   𝑘,𝑍
Allowed substitution hint:   𝑋(𝑘)

Proof of Theorem climmul
Dummy variables 𝑢 𝑣 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 climadd.1 . 2 𝑍 = (ℤ𝑀)
2 climadd.2 . 2 (𝜑𝑀 ∈ ℤ)
3 climadd.4 . . 3 (𝜑𝐹𝐴)
4 climcl 14607 . . 3 (𝐹𝐴𝐴 ∈ ℂ)
53, 4syl 17 . 2 (𝜑𝐴 ∈ ℂ)
6 climadd.7 . . 3 (𝜑𝐺𝐵)
7 climcl 14607 . . 3 (𝐺𝐵𝐵 ∈ ℂ)
86, 7syl 17 . 2 (𝜑𝐵 ∈ ℂ)
9 mulcl 10336 . . 3 ((𝑢 ∈ ℂ ∧ 𝑣 ∈ ℂ) → (𝑢 · 𝑣) ∈ ℂ)
109adantl 475 . 2 ((𝜑 ∧ (𝑢 ∈ ℂ ∧ 𝑣 ∈ ℂ)) → (𝑢 · 𝑣) ∈ ℂ)