Question: An entrepreneur designing a sustainable irrigation system models soil moisture retention with a function $ f $ such that $ f(x + y) + f(x - y) = 2f(x) + 2f(y) $ for all real $ x, y $, and $ f(1) = 3 $. Find $ f(5) $.

Mon, 04 May 2026 07:31:06 +0000

Content under review