Theorem 3lt4

Description: 3 is less than 4. (Contributed by Mario Carneiro, 15-Sep-2013)

	Ref	Expression
Assertion	3lt4	$$⊢3<4$$

Proof

Step	Hyp	Ref	Expression
1		3re	$$⊢3\in ℝ$$
2	1	ltp1i	$$⊢3<3+1$$
3		df-4	$$⊢4=3+1$$
4	2 3	breqtrri	$$⊢3<4$$