Compfiles: Catalog Of Math Problems Formalized In Lean

Singapore2019P7


import Mathlib

/-!
# Singapore Math Olympiad (Senior) 2019 (Round 1), Problem 7

http://www.realsutra.com/limjeck/SMO_Senior_2019.pdf

Suppose that $\tan x = 5$. Find the value of $\frac{6 + \sin 2x}{1 + \cos 2x}$.
-/
open Real

namespace Singapore2019R1P7

noncomputable /- determine -/ abbrev solution : ℝ := sorry

theorem singapore2019_r1_p7 (x : ℝ) (hx : tan x = 5) :
    (6 + sin (2 * x)) / (1 + cos (2 * x)) = solution := sorry

This problem has a complete formalized solution.

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