I figured that step out but I am stuck again :/

The original question was: find

det x y z t

---- y z t x

---- z t x y

---- t x y z

as a product of linear factors

We end up with

(x+y+z+t)(x-y+z-t)det (t-y-z+x) 2(x-z)

----------------------- (y-t) --- (y+z-t-x)

Which is easy enough to solve I thought...

BUT, they give the final answer as -(x+y+z+t)(x+iy-z-it)(x-y+z-t)(x-iy-z+it)

WHERE DID THE iS COME FROM? Madness. Help please!