lean_workbook_plus_61852

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by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

$R = \frac{1}{\cos \alpha} = \frac{1}{\cos(\pi/3)} = 2$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_61852 : 1 / Real.cos (π / 3) = 2   :=  by sorry

Source