Metamath Proof Explorer


Theorem divgt0i

Description: The ratio of two positive numbers is positive. (Contributed by NM, 16-May-1999)

Ref Expression
Hypotheses ltplus1.1 ⊢ A ∈ ℝ
prodgt0.2 ⊢ B ∈ ℝ
Assertion divgt0i ⊢ 0 < A ∧ 0 < B → 0 < A B

Proof

Step Hyp Ref Expression
1 ltplus1.1 ⊢ A ∈ ℝ
2 prodgt0.2 ⊢ B ∈ ℝ
3 divgt0 ⊢ A ∈ ℝ ∧ 0 < A ∧ B ∈ ℝ ∧ 0 < B → 0 < A B
4 2 3 mpanr1 ⊢ A ∈ ℝ ∧ 0 < A ∧ 0 < B → 0 < A B
5 1 4 mpanl1 ⊢ 0 < A ∧ 0 < B → 0 < A B