A probability density function on the interval [1/e^2, 1] is given by f(x) = a/x, and outside this interval the value of the function is zero. The value of a is ___________.

GATE 2016 · Engineering Mathematics · Continuous Distribution · medium

Answer: 0.5

  1. Set up the normalization integral: integral_{1/e^2}^{1} (a/x) dx = 1 => a * [ln x]_{1/e^2}^{1} = 1
  2. Evaluate the definite integral: a * (ln(1) - ln(1/e^2)) = a * (0 - (-2)) = 2a = 1
  3. Solve for a: a = 1/2 = 0.5