GENERALIZED TRICOMI PROBLEM FOR THE EQUATION OF MIXED TYPE OF SECOND ORDER

Ⅰ. INTRODUCTION In domain （?）（=（?）+∪（?）-） we consider the equation of mixed type Lw≡ k（x,y）wxx+wyy+α（x,y）wx+β（x,y）wy+γ（x,y）w=f（x,y）, （1）where the function k（x, y） satisfies the conditions: yk >0, when y≠0, k（x,0）=0, k∈C1（（?））, the function α,β, γ∈C（（?））, f∈L2（（?））. Let the outer boundary