Given the function f (x) = LNX + (1-x) / ax, a is a constant greater than zero For any integer greater than one, lnn > 1 / 2 + 1 / 3 + 1/N

When a = 1, f (x) = LNX + (1-x) / x = LNX + 1 / X-1, f '(x) = 1 / X-1 / x ^ 2 = (x-1) / x ^ 2, obviously, when x > 1, the function increases; 00, LNX > 1-1 / X. let x = 2,3 / 2,4 / 3 The results show that LN2 > 1-1 / 2 = 1 / 2, Ln3 / 2 > 1-2 / 3 = 1 / 3, ln4 / 3 > 1-3 / 4 = 1 / 4 l...

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