lean_workbook_plus_38312

Proved

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

Given $t = a+b, p = ab$ and $2t^2-2p=1$ , prove that $t^2 \leq \frac{2}{3}$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_38312 (a b t p : ℝ) (h₁ : t = a + b) (h₂ : p = a * b) (h₃ : 2 * t ^ 2 - 2 * p = 1) : t ^ 2 ≤ 2 / 3   :=  by sorry

Source