Metamath Proof Explorer


Theorem 1lt8

Description: 1 is less than 8. (Contributed by Mario Carneiro, 15-Sep-2013)

Ref Expression
Assertion 1lt8
|- 1 < 8

Proof

Step Hyp Ref Expression
1 1lt2
 |-  1 < 2
2 2lt8
 |-  2 < 8
3 1re
 |-  1 e. RR
4 2re
 |-  2 e. RR
5 8re
 |-  8 e. RR
6 3 4 5 lttri
 |-  ( ( 1 < 2 /\ 2 < 8 ) -> 1 < 8 )
7 1 2 6 mp2an
 |-  1 < 8