Metamath Proof Explorer


Theorem xnn0xrnemnf

Description: The extended nonnegative integers are extended reals without negative infinity. (Contributed by AV, 10-Dec-2020)

Ref Expression
Assertion xnn0xrnemnf ( 𝐴 ∈ ℕ0* → ( 𝐴 ∈ ℝ*𝐴 ≠ -∞ ) )

Proof

Step Hyp Ref Expression
1 xnn0xr ( 𝐴 ∈ ℕ0*𝐴 ∈ ℝ* )
2 xnn0nemnf ( 𝐴 ∈ ℕ0*𝐴 ≠ -∞ )
3 1 2 jca ( 𝐴 ∈ ℕ0* → ( 𝐴 ∈ ℝ*𝐴 ≠ -∞ ) )