lean_workbook_plus_34341

Open

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

Prove the logarithmic identity: $\log_a b+\log_a c=\log_a bc$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_34341 : ∀ a b c : ℝ, a > 0 ∧ b > 0 ∧ c > 0 → Real.logb a b + Real.logb a c = Real.logb a (b * c)   :=  by sorry

Source