pith. machine review for the scientific record. sign in
lemma proved tactic proof

golden_ratio_gt_one

show as:
view Lean formalization →

No prose has been written for this declaration yet. The Lean source and graph data below render without it.

generate prose now

formal statement (Lean)

 103private lemma golden_ratio_gt_one : 1 < (1 + Real.sqrt 5) / 2 := by

proof body

Tactic-mode proof.

 104  have h5 : 1 < Real.sqrt 5 := by
 105    rw [show (1:ℝ) = Real.sqrt 1 from Real.sqrt_one.symm]
 106    exact Real.sqrt_lt_sqrt (by norm_num) (by norm_num)
 107  linarith
 108
 109/-- Critical exponent is positive. -/

used by (1)

From the project-wide theorem graph. These declarations reference this one in their body.

depends on (5)

Lean names referenced from this declaration's body.