15.2.3 One dimensional random variables and their characteristics

Problem: The distribution density of the random variable \( \mathrm{X} \) is given: \[ f(x)=\left\{\begin{array}{cc} 0, & x \leq 2 \\ 2 x-4, & 23 \end{array}\right. \] Find \( F(x), M(x), D(x), \sigma(x) \).