Elliptic, Hyperbolic And Mixed Complex Equations With Parabolic Degeneracy: Including Tricomi-bers And Tricomi-frankl-rassias Problems

In the recent half-century, many mathematicians have investigated various problems on several equations of mixed type and obtained interesting results, with important applications to gas dynamics. However, the Tricomi problem of general mixed type equations of second order with parabolic degeneracy has not been completely solved, particularly the Tricomi and Frankl problems for general Chaplygin equation in multiply connected domains posed by L Bers, and the existence, regularity of solutions of