Theorems · Theorem · real analysis
Real.cos_pi_div_five
Real.cos (Real.pi / 5) = (1 + √5) / 4
The cosine of π / 5 is (1 + √5) / 4.
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- 0 results in Mathlib
- Foundations
- Depth 180 from the axioms · uses propext, Classical.choice, Quot.sound
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