Metamath Proof Explorer


Theorem resum2sqrp

Description: The sum of the square of a nonzero real number and the square of another real number is a positive real number. (Contributed by AV, 2-May-2023)

Ref Expression
Hypothesis resum2sqcl.q ⊢ Q = A 2 + B 2
Assertion resum2sqrp ⊢ A ∈ ℝ ∧ A ≠ 0 ∧ B ∈ ℝ → Q ∈ ℝ +

Proof

Step Hyp Ref Expression
1 resum2sqcl.q ⊢ Q = A 2 + B 2
2 1 resum2sqcl ⊢ A ∈ ℝ ∧ B ∈ ℝ → Q ∈ ℝ
3 2 adantlr ⊢ A ∈ ℝ ∧ A ≠ 0 ∧ B ∈ ℝ → Q ∈ ℝ
4 1 resum2sqgt0 ⊢ A ∈ ℝ ∧ A ≠ 0 ∧ B ∈ ℝ → 0 < Q
5 3 4 elrpd ⊢ A ∈ ℝ ∧ A ≠ 0 ∧ B ∈ ℝ → Q ∈ ℝ +