Quasilinear equations of mixed type （Ⅰ ）——Oblique derivative problems

摘要

＜正＞ The oblique derivative boundary value problem for quasitinear second-order equations of mixed （ el liptic-hyperbolic） type is studied. Firstly the representation of solutions of the above boundary value problem, is given, and then the uniqueness and existence of solutions of the above problem are proved In the meantime a priori estimates of solutions for the problem are obtained.