例:若x=123456789×123456786,
y=123456788×123456787,试比较x,y的大小.
解:设123456788=a,则x=(a+1)(a-2)
, ∴x<y.
若x=20242024×20242028-20242025×20242027,y=20242025×20242029-20242026×20242028,试比较x,y的大小.