9999999×9999999简便计算

问题描述:

9999999×9999999简便计算
等待复制;(9999999+1)×9999999-9999999=999999900000000-9999999=9999998900000001

原式=(100000000-1)x9999999
=100000000x9999999-9999999
=999999900000000-9999999
=999999890000001