作业帮o.9+0.99+0.999+.+0.999999999 简便计算
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/29 13:37:29
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o.9+0.99+0.999+.+0.999999999 简便计算
o.9+0.99+0.999+.+0.999999999 简便计算
o.9+0.99+0.999+.+0.999999999 简便计算
0.9+0.99+0.999+.+0.999999999
= 1-0.1 + 1-0.01 + ... + 1-0.000000001
= 1*9 - (0.1+0.01+...+0.000000001)
= 9 - 0.111111111
= 8.888888889
=1-0.1+1-0.01+10.001+……+1-0.000000001
=9-0.111111111
=8.888888889
o.9+0.99+0.999+......+0.999999999
=1-0.1 + 1-0.01 +1- 0.001 +1-0.000000001
=9- 0.111111111
=8.888888889