问题 解答题
计算:
1
6
+
1
12
+
1
20
+
1
30
+
1
42
+
1
56
+
1
72
+
1
90

1
2
+
1
4
+
1
8
+…+
1
128
+
1
256
答案

1
6
+
1
12
+
1
20
+
1
30
+
1
42
+
1
56
+
1
72
+
1
90

=

1
2×3
+
1
3×4
+
1
4×5
+
1
5×6
+
1
6×7
+
1
7×8
+
1
8×9
+
1
9×10

=

1
2
-
1
3
+
1
3
-
1
4
+…+
1
9
-
1
10

=

1
2
-
1
10

=

2
5

1
2
+
1
4
+
1
8
+…+
1
128
+
1
256

=(1-

1
2
)+(
1
2
-
1
4
)+(
1
4
-
1
8
)+…+(
1
128
-
1
256
),

=1-

1
256

=

255
256

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