cp2设f(x)=4x2+x2-, g(r) 31 x+iX X 则其首一最大公因式 (f(x),g(x)= 且 ux ,v(x)=使 u(xf(+v(xg(=(f(x),g(x) 又(v(x),1(x)=18 ( ) , ( ) , 2 1 2 2 1 4 3 1 4 1 2 2 1 4 4 1 4 1 = + − − = + − g x x x x 设 f x x x ( ) ( ) ( ) ( ) ( ( ), ( )). ( ) ( ) u x f x v x g x f x g x u x v x + = 且有 = ， = 使得 ( f (x), g(x)) = . 则其首一最大公因式 又（u(x)，v(x)）= . exp2