Also E^2
does not calculate, just as DawsonF[5]
and Dawson[1+I]
. They are exact symbolic numbers for which no automatic calculations are done, if you evaluate them in isolation. However, you may try to find different symbolic expressions, for example with
DawsonF[5] // FunctionExpand
DawsonF[1 + I] // FunctionExpand
The floating point in Dawson[5.0]
triggers numeric algorithms. You can do it also with N[DawsonF[5]]
.