theorem
proved
phi_lt_162
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IndisputableMonolith.Numerics.Interval.Tactic on GitHub at line 76.
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73 exact lt_of_lt_of_le h1 h.1
74
75/-- Example: Prove φ < 1.62 (using interval hi = 1619/1000) -/
76theorem phi_lt_162 : (1 + Real.sqrt 5) / 2 < (1.62 : ℝ) := by
77 have h := phi_in_phiInterval
78 -- phiInterval.hi = 1619/1000 < 1.62
79 have h1 : ((1619 / 1000 : ℚ) : ℝ) < (1.62 : ℝ) := by norm_num
80 exact lt_of_le_of_lt h.2 h1
81
82end IndisputableMonolith.Numerics.Interval