With the development of quotient rings of polynomial rings, the concept behind an imaginary number became more substantial, but then one also finds other imaginary numbers such as the j of tessarines which has a square of +1.
Razvojem kvocijenata polinomijalnih prstenova koncept imaginarnoga broja je postao značajniji, dok su se našli i drugi imaginarni brojevi kao j od tesarina čiji je kvadrat +1.