问题
填空题
计算:
|
答案
-11…1 2n 22…2 n
=
×10n+11…1 n
-11…1 n 22…2 n
=
×10n-11…1 n 11…1 n
=
×(10n-1)11…1 n
=
×9×11…1 n 11…1 n
=3×
=11…1 n 33…3 n
=10n-1 3
计算:
|
-11…1 2n 22…2 n
=
×10n+11…1 n
-11…1 n 22…2 n
=
×10n-11…1 n 11…1 n
=
×(10n-1)11…1 n
=
×9×11…1 n 11…1 n
=3×
=11…1 n 33…3 n
=10n-1 3