Is is permissible to write an acceleration vector like they do in physics? So instead of the AP style <3t, t-4>, the vector could be written as (3t)i+(t-4)j?
and array instead of pmatrix:
The <br\> thing happens when you put pieces of the array on separate lines.
Actually, it seems that pmatrix works:
In fact, I think I like that better than what I got before with array.