已知x=9.876543×3.456789,y=9.876544×3.456788,那么x(  )y. A.> B.= C.<

问题描述:

已知x=9.876543×3.456789,y=9.876544×3.456788,那么x(  )y.
A. >
B. =
C. <

x=9.876543×3.456789
=9.876543×(3.456788+0.000001)
=9.876543×3.456788+9.876543×0.000001
y=9.876544×3.456788
=(9.876543+0.000001)×3.456788
=9.876543×3.456788+0.000001×3.0456788
又9.876543>3.0456788,
所以9.876543×3.456788+9.876543×0.000001>9.876543×3.456788+0.000001×3.0456788,
即 x>y.
故选:A.