${\displaystyle \underset{-}{\overset{}{}}}\frac{x{e}^{-\frac{(x-a{)}^2}{2b^2}}}{\sqrt[\phantom{2}]{2}b}dx,$ Use $u$ substitution $to$ solve $it,u^2=\frac{(x-a{)}^2}{2b^2},$ you will ended $up$ with $E(\stackrel{}{x})=$ a and sigma $=bb$ and a are constants, just try $to$ solve the integral. That $is$ all the information I have