... +− = +2 22 22 22 2 3 3 2 3 3 3 2 2 3 32 2 3 32 2 3 3 3 2 3 2 4 ,21, 3 3 3 5 .5 7,22, 3 4. 3 4 0, 23, 2 3 .2,24,2 2 . 3 4,25, 3 5 2 6 .2,26,5 2 4 3 .227,x y y xx y xy y ... ++ = + −−( )( )( )2 3 32 22 3 3 22 3 3 3 3 2 3 3 3 3 2 2 3 3 3 3 2 2 3 2 2 3 32 5 ,2.6 4 3 ,7,2 5.7 3 ,8,4 6.,9, 3 6.10 4 5 ,10,1 2 3 .10 5 4 ,11,y xx yx y y x ... =− =+ = 3 2 3 2 2 3 2 3 2 2 3 2 3 2 22 3 32 2 3 2 3 2 22 3 32 22 ,17,2 3 7 .16 2 ,18, 3 5 .2 3 ,19, 3 .2 3 ,20, 3 . 3 4 ,21,2 3 .4 3 0,22,.4 23, x xy yx y x y xyx...