span align = "justify" >? 0 маємо:
F = ? 1 (x + b 1 / ? 1 ) 2 + ? 1 (y + b 2 / ? 2 ) < span align = "justify"> 2 + 2b 3 z + ( b 0 - (b 1 ) 2 / ? 1 - (b 2 ) 2 / ? 2 ) = ? 1 (x ') 2 + ? < span align = "justify"> 2 (y ') 2 + 2b 3 z + ? = ? 1 x 2 + ? 2 < span align = "justify"> y 2 + 2b 3 (z + ? /2b 3 ) = ? 1 x 2 + ? 2 y 2 + 2b 3 z '.
(III) При ? 3 = b
