[quote=@Vampyr]
<Snipped quote by whizzball1>

....ew.
[/quote]

Eh. I think it's mostly just to instil the concept of solving any sized determinants. The author of my book likes to make us play with things and try to figure things out--he doesn't give information about how to solve the 4x4 determinant except the table of minors. It's pretty simple, though.