Noun
tessarine (plural tessarines)
(mathematics) A hypercomplex number of the form
t
=
w
+
x
i
+
y
j
+
z
k
,
w
,
x
,
y
,
z
∈
R
{\displaystyle t=w+xi+yj+zk,\quad w,x,y,z\in \mathbb {R} }
where
i
j
=
j
i
=
k
,
i
2
=
−
1
,
j
2
=
+
1.
{\displaystyle ij=ji=k,\quad i^{2}=-1,\quad j^{2}=+1.}