Extending the number system from complex numbers, (a+bi), to 4-D
hypercomplex numbers, (a+bi+cj+dk), leads to a multiplication
table such as:
(A) i^2=j^2=-1, ij=ji=k, k^2=+1, ik=ki=-j, jk=kj=-i.
Note that these hypercomplex numbers are commutative and have elementary functions.
We...