Zeros of a Shifted Log

Problem

Let f(x)=∣lg⁡x∣−kx−2f(x)=|\lg x|-kx-2. Determine, with proof, which of the following claims are true.

1. If k=0k=0, then f(x)f(x) has two zeros. 2. There exists k<0k<0 such that f(x)f(x) has exactly one zero. 3. There exists k<0k<0 such that f(x)f(x) has three zeros. 4. There exists k>0k>0 such that f(x)f(x) has three zeros.

Answer

Solution

Difficulty7/10
Topicsfunctions, calculus, Monotonicity, Logarithms, Casework

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