Prove2Me

lean_workbook_plus_60336

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

Prove that cos⁡36∘−cos⁡72∘=sin⁡54∘−sin⁡18∘\cos 36^\circ-\cos 72^\circ=\sin 54^\circ-\sin 18^\circ

Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_60336 : Real.cos (36 * Real.pi / 180) - Real.cos (72 * Real.pi / 180) = Real.sin (54 * Real.pi / 180) - Real.sin (18 * Real.pi / 180)   :=  by sorry
Source
https://huggingface.co/datasets/internlm/Lean-Workbook

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