1/2+1/4+1/8+1/16+1/32+1/64.

问题描述:

1
2
+
1
4
+
1
8
+
1
16
+
1
32
+
1
64

方法1:

1
2
+
1
4
+
1
8
+
1
16
+
1
32
+
1
64

=
3
4
+
1
8
+
1
16
+
1
32
+
1
64

=
7
8
+
1
16
+
1
32
+
1
64

=
15
16
+
1
32
+
1
64

=
31
32
+
1
64

=
63
64

方法2:
1
2
+
1
4
+
1
8
+
1
16
+
1
32
+
1
64
=
1
2
1
64
×
1
2
1−
1
2
=
63
64