Description: A positive Pell solution is a positive real. (Contributed by Stefan O'Rear, 19-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | pell14qrrp | ⊢ ( ( 𝐷 ∈ ( ℕ ∖ ◻NN ) ∧ 𝐴 ∈ ( Pell14QR ‘ 𝐷 ) ) → 𝐴 ∈ ℝ+ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pell14qrre | ⊢ ( ( 𝐷 ∈ ( ℕ ∖ ◻NN ) ∧ 𝐴 ∈ ( Pell14QR ‘ 𝐷 ) ) → 𝐴 ∈ ℝ ) | |
2 | pell14qrgt0 | ⊢ ( ( 𝐷 ∈ ( ℕ ∖ ◻NN ) ∧ 𝐴 ∈ ( Pell14QR ‘ 𝐷 ) ) → 0 < 𝐴 ) | |
3 | 1 2 | elrpd | ⊢ ( ( 𝐷 ∈ ( ℕ ∖ ◻NN ) ∧ 𝐴 ∈ ( Pell14QR ‘ 𝐷 ) ) → 𝐴 ∈ ℝ+ ) |