Metamath Proof Explorer


Theorem xrsmul

Description: The multiplication operation of the extended real number structure. (Contributed by Mario Carneiro, 21-Aug-2015)

Ref Expression
Assertion xrsmul ·e = ( .r ‘ ℝ*𝑠 )

Proof

Step Hyp Ref Expression
1 xmulf ·e : ( ℝ* × ℝ* ) ⟶ ℝ*
2 xrex * ∈ V
3 2 2 xpex ( ℝ* × ℝ* ) ∈ V
4 fex2 ( ( ·e : ( ℝ* × ℝ* ) ⟶ ℝ* ∧ ( ℝ* × ℝ* ) ∈ V ∧ ℝ* ∈ V ) → ·e ∈ V )
5 1 3 2 4 mp3an ·e ∈ V
6 df-xrs *𝑠 = ( { ⟨ ( Base ‘ ndx ) , ℝ* ⟩ , ⟨ ( +g ‘ ndx ) , +𝑒 ⟩ , ⟨ ( .r ‘ ndx ) , ·e ⟩ } ∪ { ⟨ ( TopSet ‘ ndx ) , ( ordTop ‘ ≤ ) ⟩ , ⟨ ( le ‘ ndx ) , ≤ ⟩ , ⟨ ( dist ‘ ndx ) , ( 𝑥 ∈ ℝ* , 𝑦 ∈ ℝ* ↦ if ( 𝑥𝑦 , ( 𝑦 +𝑒 -𝑒 𝑥 ) , ( 𝑥 +𝑒 -𝑒 𝑦 ) ) ) ⟩ } )
7 6 odrngmulr ( ·e ∈ V → ·e = ( .r ‘ ℝ*𝑠 ) )
8 5 7 ax-mp ·e = ( .r ‘ ℝ*𝑠 )