1)1×1=1,
11×11=121,
111×111=12321,
1111×1111=1234321.
(2)2+9×1=11,
3+9×12=111,
4+9×123=1111,
5+9×1234=11111;
故答案为:1234321,11111.
1)1×1=1,
11×11=121,
111×111=12321,
1111×1111=1234321.
(2)2+9×1=11,
3+9×12=111,
4+9×123=1111,
5+9×1234=11111;
故答案为:1234321,11111.