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If \(f(x) = \frac{|x|}{x^{2}}\) , then \(f'(2)\) is equal to

  • A.\(\frac{1}{2}\)
  • B.\(\frac{1}{4}\)
  • C.\(-\frac{1}{2}\)
  • D.\(-\frac{1}{4}\)
  • E.\(-\frac{1}{6}\)

Answer: D

\(f'(2)\) is \(-\frac{1}{4}\).

Near x = 2, x is positive, so \(|x| = x\) and \(f(x) = \frac{x}{x^{2}} = \frac{1}{x}\).

\[ f'(x) = -\frac{1}{x^{2}} \Rightarrow f'(2) = -\frac{1}{4} \]

\(\frac{1}{4}\) drops the minus sign, and \(-\frac{1}{2}\) is \(-\frac{1}{x}\) instead of \(-\frac{1}{x^{2}}\). The modulus matters only for negative x, where \(f(x) = -\frac{1}{x}\) and the derivative would be \(+\frac{1}{x^{2}}\); at x = 2 that branch is not used.

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