Metamath Proof Explorer


Theorem 4lt5

Description: 4 is less than 5. (Contributed by Mario Carneiro, 15-Sep-2013)

Ref Expression
Assertion 4lt5 4 < 5

Proof

Step Hyp Ref Expression
1 4re 4 ∈ ℝ
2 1 ltp1i 4 < ( 4 + 1 )
3 df-5 5 = ( 4 + 1 )
4 2 3 breqtrri 4 < 5