Generally, there is a step with the first question. The first problem of this kind of problem is generally to find the tangent equation, construct the h(x)=f(x)- tangent equation greater than or equal to 0, and assign a value to solve it.

The first problem is to find the tangent equation y = (e 2/4- 1) x,

Then h (x) = e x/x-x-(e 2/4-1) x = e x/x-e 2x/4 ≥ 0 holds,

E (x-2)/x ≥ x/4,

Assignment 1/e ≥ 1/4, 1/2 ≥ 2/4, e/3 ≥ 3/4, e 2/4 ≥ 4/4, ... e (n-2)/n ≥ n/4,

Cumulative1/e+1/2+e/3+...+e (n-2)/n ≥ (1+2+3+...+n)/4 = n (n+1.

This is not a scaling problem.