ax as ax an ax Ba5 oOo on n ao ay as ay an Oy 00(1a)05_102 Ox2 a5( ox Ba5 00(00ma0 Oy2an(n丿ay =P0m1            =     +     =   1 ˆ ˆ ˆ x x x            =     +     =   y y y ˆ ˆ ˆ 2 2 2 2 1 1 ˆ            =               =   x x 2 2 2 2 ˆ           =               =   y y