lean_workbook_plus_70282

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

And $(1+t^2_1)(1+t^2_2)\geq (t_1+t_2)^2$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_70282 : ∀ t1 t2 : ℝ, (1 + t1^2) * (1 + t2^2) ≥ (t1 + t2)^2   :=  by sorry

Source