when to use $e(x]$ for the mean when to use e(x)$ for the mean what variable is used for the mean of a binomial distribution when do i use u(x)$ what is the difference between e(x)$ and mean why do I use $e(x)$ when do you use $mu$ for the mean? when to use $e(x)$ and how to use it for mean? what is the function for e(x)$ when is e(x) used in the mean what is the purpose of $e(x)$ what is the value of $e(xx)$ in a normal distribution when to use $e(x)$ in a function when to use mu$ for mean when to use mu$ for e(x)? when to use mu$ what is the meaning of mu$ how to use the variable mu for mean when is $mu_x$ used in terms of the mean when to use mu$