问题 解答题
(1+
1
2
)×(1-
1
2
)×(1+
1
3
)×(1-
1
3
)×…×(1+
1
100
)×(1-
1
100
答案

(1+

1
2
)×(1-
1
2
)×(1+
1
3
)×(1-
1
3
)×…×(1+
1
100
)×(1-
1
100

=

3
2
×
1
2
×
4
3
×
2
3
×
5
4
×
3
4
×…×
101
100
×
99
100

=

1
2
×
3
2
×
2
3
×
4
3
×
3
4
×
5
4
×…×
99
100
×
101
100

=

1
2
×
101
100

=

101
200

单项选择题
单项选择题