Metamath Proof Explorer


Theorem xrslt

Description: The "strictly less than" relation for the extended real structure. (Contributed by Thierry Arnoux, 30-Jan-2018)

Ref Expression
Assertion xrslt < = ( lt ‘ ℝ*𝑠 )

Proof

Step Hyp Ref Expression
1 dflt2 ⊢ < = ( ≤ ∖ I )
2 xrsex ⊢ ℝ*𝑠 ∈ V
3 xrsle ⊢ ≤ = ( le ‘ ℝ*𝑠 )
4 eqid ⊢ ( lt ‘ ℝ*𝑠 ) = ( lt ‘ ℝ*𝑠 )
5 3 4 pltfval ⊢ ( ℝ*𝑠 ∈ V → ( lt ‘ ℝ*𝑠 ) = ( ≤ ∖ I ) )
6 2 5 ax-mp ⊢ ( lt ‘ ℝ*𝑠 ) = ( ≤ ∖ I )
7 1 6 eqtr4i ⊢ < = ( lt ‘ ℝ*𝑠 )