Metamath Proof Explorer


Axiom ax-mulrcl

Description: Closure law for multiplication in the real subfield of complex numbers. Axiom 7 of 22 for real and complex numbers, justified by Theorem axmulrcl . Proofs should normally use remulcl instead. (New usage is discouraged.) (Contributed by NM, 22-Nov-1994)

Ref Expression
Assertion ax-mulrcl ( ( 𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → ( 𝐴 · 𝐵 ) ∈ ℝ )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cA ⊢ 𝐴
1 cr ⊢ ℝ
2 0 1 wcel ⊢ 𝐴 ∈ ℝ
3 cB ⊢ 𝐵
4 3 1 wcel ⊢ 𝐵 ∈ ℝ
5 2 4 wa ⊢ ( 𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ )
6 cmul ⊢ ·
7 0 3 6 co ⊢ ( 𝐴 · 𝐵 )
8 7 1 wcel ⊢ ( 𝐴 · 𝐵 ) ∈ ℝ
9 5 8 wi ⊢ ( ( 𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → ( 𝐴 · 𝐵 ) ∈ ℝ )