IMC 1995 · Problem 3

Day 115 points2nd IMC · Plovdiv, Bulgaria

Statement

Let ff be twice continuously differentiable on (0,+∞)(0, +\infty) such that lim⁡x→0+f′(x)=−∞\lim\limits_{x \to 0+} f'(x) = -\infty and lim⁡x→0+f′′(x)=+∞\lim\limits_{x \to 0+} f''(x) = +\infty. Show that

lim⁡x→0+f(x)f′(x)=0.\lim_{x \to 0+} \frac{f(x)}{f'(x)} = 0.

Official solution

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