1-2/3-2/9-2/27-2/81-2/243-2/729=_.

问题描述:

1-

2
3
-
2
9
-
2
27
-
2
81
-
2
243
-
2
729
=______.

1-

2
3
-
2
9
-
2
27
-
2
81
-
2
243
-
2
729

=1-(
2
3
+
2
9
+
2
27
+
2
81
+
2
243
+
2
729
),
=1-(1-
1
3
+
1
3
-
1
9
+
1
9
-
1
27
+
1
27
-
1
81
+
1
81
-
1
243
+
1
243
-
1
729
),
=1-(1-
1
729
),
=1-1+
1
729

=
1
729