Well as everyone here is being a dumb dumb.
For work learn both, there is no reason not to and studios vary on this kind of thing, due to budget and what the senior members prefer. but as that is probably not the answer you are looking for;
> AE for motion graphics
> Nuke for comp
As a side not, nuke is node based, and if you haven't worked in anything node based before, it will probably kick your ass for a few hours.