Metamath Proof Explorer


Theorem lerel

Description: "Less than or equal to" is a relation. (Contributed by FL, 2-Aug-2009) (Revised by Mario Carneiro, 28-Apr-2015)

Ref Expression
Assertion lerel Rel ≤

Proof

Step Hyp Ref Expression
1 lerelxr ≤ ⊆ ( ℝ* × ℝ* )
2 relxp Rel ( ℝ* × ℝ* )
3 relss ( ≤ ⊆ ( ℝ* × ℝ* ) → ( Rel ( ℝ* × ℝ* ) → Rel ≤ ) )
4 1 2 3 mp2 Rel ≤