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 ∈ ℝ
4 2re ⊢ 2 ∈ ℝ
5 8re ⊢ 8 ∈ ℝ
6 3 4 5 lttri ⊢ 1 < 2 ∧ 2 < 8 → 1 < 8
7 1 2 6 mp2an ⊢ 1 < 8