3/2+5/4+9/8+17/16+…+257/256.

问题描述:

3
2
+
5
4
+
9
8
+
17
16
+…+
257
256

3
2
+
5
4
+
9
8
+
17
16
+…+
257
256

=1+
1
2
+1+
1
4
+1+
1
8
+1+
1
16
+…+1+
1
256

=(1+1+1+1+…+1)+(
1
2
+
1
4
+
1
8
+
1
16
+…+
1
256
),
=8+(1-
1
2
+
1
2
-
1
4
+
1
4
-
1
8
+
1
8
-
1
16
+…+
1
128
-
1
256
),
=8+(1-
1
256
),
=8+
255
256

=8
255
256