`BookProof.ChapterEulerCountableChain.one_sub_condCos` (θ : ℕ → ℝ) (n : ℕ) : 1 - condCos θ n = Real.sin (θ n) ^ 2

Proved

BookProof.ChapterEulerCountableChain.one_sub_condCos

by leonardopedro · Oct 8, 2026 · Mathlib 0df444a (Lean v4.33.1)

theoremstimepiece

Prove the following Lean 4 theorem from ChapterEulerCountableChain.

BookProof.ChapterEulerCountableChain.one_sub_condCos (θ : ℕ → ℝ) (n : ℕ) : 1 - condCos θ n = Real.sin (θ n) ^ 2

Formalization note: Lean 4 identifier BookProof.ChapterEulerCountableChain.one_sub_condCos.

Preamble

-- Generated from ChapterEulerCountableChain.lean — theorem BookProof.ChapterEulerCountableChain.one_sub_condCos
import Mathlib
import Definitions.Def_ChapterEulerCountableChain
open BookProof.ChapterEulerCountableChain


open scoped BigOperators
open Filter Topology

Formal statement

theorem BookProof.ChapterEulerCountableChain.one_sub_condCos (θ : ℕ → ℝ) (n : ℕ) :
    1 - condCos θ n = Real.sin (θ n) ^ 2 := by sorry

View graph