Metamath Proof Explorer


Theorem lerelxr

Description: "Less than or equal to" is a relation on extended reals. (Contributed by Mario Carneiro, 28-Apr-2015)

Ref Expression
Assertion lerelxr ≤ ⊆ ( ℝ* × ℝ* )

Proof

Step Hyp Ref Expression
1 df-le ≤ = ( ( ℝ* × ℝ* ) ∖ < )
2 difss ( ( ℝ* × ℝ* ) ∖ < ) ⊆ ( ℝ* × ℝ* )
3 1 2 eqsstri ≤ ⊆ ( ℝ* × ℝ* )