Metamath Proof Explorer

Theorem 9lt10

Description: 9 is less than 10. (Contributed by Mario Carneiro, 8-Feb-2015) (Revised by AV, 8-Sep-2021)

Ref Expression
Assertion 9lt10 
|- 9 < ; 1 0

Proof

Step Hyp Ref Expression
1 9re 
 |-  9 e. RR
2 1 ltp1i 
 |-  9 < ( 9 + 1 )
3 9p1e10 
 |-  ( 9 + 1 ) = ; 1 0
4 2 3 breqtri 
 |-  9 < ; 1 0