By means of the application of annihilating entire functions of an operator, the bilateral quadratic equation in operators A + BT +TC + TDT = 0, is changed into an unilateral linear equation, obtaining conditions under which the solutions of such linear equation satisfy the quadratic equation.
@article{urn:eudml:doc:38892, title = {Sobre la ecuaci\'on cuadr\'atica en operadores A + BT +TC + TDT = 0.}, journal = {Stochastica}, volume = {7}, year = {1983}, pages = {145-154}, zbl = {0573.47012}, mrnumber = {MR0766697}, language = {es}, url = {http://dml.mathdoc.fr/item/urn:eudml:doc:38892} }
Hernández, Vicente; Jódar, Lucas. Sobre la ecuación cuadrática en operadores A + BT +TC + TDT = 0.. Stochastica, Tome 7 (1983) pp. 145-154. http://gdmltest.u-ga.fr/item/urn:eudml:doc:38892/