Metamath Proof Explorer


Theorem zssxr

Description: The integers are a subset of the extended reals. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Assertion zssxr ℤ ⊆ ℝ*

Proof

Step Hyp Ref Expression
1 zssre ℤ ⊆ ℝ
2 ressxr ℝ ⊆ ℝ*
3 1 2 sstri ℤ ⊆ ℝ*