I'm not sure where I'm going wrong here. I'm given a particle's acceleration as a function of t, an initial velocity, and an initial position:

I have to find the particle's velocity v(t) so I integrated each component and added the initial velocity:

v(t) =

For some reason this is being marked wrong by the homework site. Can you tell me why? Am I not integrating correctly or adding the initial velocity incorrectly or something. Thanks very much for any help.