Given the probability density function f(x)=1xln(6)\displaystyle {f{{\left({x}\right)}}}=\frac{{1}}{{{x}{\ln{{\left({6}\right)}}}}} over the interval [0.5,3]\displaystyle {\left[{0.5},{3}\right]}, find the expected value, the mean, the variance and the standard deviation.

Expected value:  

Mean:  

Variance:  

Standard Deviation: