symm
a b c : ℤα
x y : ℝ
this : |y - ↑(round ((2⁻¹ * rt7)⁻¹ * y)) * (2⁻¹ * rt7)| ≤ 2⁻¹ * (2⁻¹ * rt7)
⊢ rt7 * (↑(ofNat 1) / ↑4) = |rt7 * (↑(ofNat 1) / ↑4)|
a b c : ℤα
x y : ℝ
this : |y - ↑(round ((2⁻¹ * rt7)⁻¹ * y)) * (2⁻¹ * rt7)| ≤ 2⁻¹ * (2⁻¹ * rt7)
⊢ |rt7 * (↑(ofNat 1) / ↑4)| = rt7 * (↑(ofNat 1) / ↑4)