Sum components of a vector in Wolfram|Alpha?

Questions
,
1

u={1,2,3} ; Sum[u]

This isn’t giving 6: http://www.wolframalpha.com/input/?i=u%3D%7B1,2,3%7D+;+Sum%5Bu%5D

I think I’m doing it right: Sum

What gives?

2

Try this

u={1,2,3} sum components of u

http://www.wolframalpha.com/input/?i=u%3D%7B1,2,3%7D+sum+components+of+u