The function f (x) = ln (x + 1) - ax + (1-A) / (x + 1) (A & gt; 0.5) (1) is known when the curve y = | Math enthusiast | Mathematical art

The function f (x) = ln (x + 1) - ax + (1-A) / (x + 1) (A & gt; 0.5) (1) is known when the curve y =

1 / (1 + x) - A - (1-A) / ((x + 1) * (x + 1)), substituting x = 1, the slope is 0.25-0.75 * a, and the product of 2 is - 1, so a = 1;
2. Derivative & gt; 0, derivative reduction (t-1) (at + A-T), a & gt; 1, decreasing interval (A / (1-A), 1), the rest is increasing, 0.5a1, reverse
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