Theorem 6lt8

Description: 6 is less than 8. (Contributed by Mario Carneiro, 15-Sep-2013)

	Ref	Expression
Assertion	6lt8	|- 6 < 8

Proof

Step	Hyp	Ref	Expression
1		6lt7	|- 6 < 7
2		7lt8	|- 7 < 8
3		6re	|- 6 e. RR
4		7re	|- 7 e. RR
5		8re	|- 8 e. RR
6	3 4 5	lttri	|- ( ( 6 < 7 /\ 7 < 8 ) -> 6 < 8 )
7	1 2 6	mp2an	|- 6 < 8