theorem proved term proof

`phi_psi_sum`

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

formal statement (Lean)

 101theorem phi_psi_sum : φ + ψ = 1 := by

Term-mode proof.

 102  unfold φ ψ; ring
 103
 104/-- **THEOREM: φ − ψ = √5** -/