44...44(2n个)-88...88(n个)
=4×（111.1(2n个)-2×11...1(n个)）
=4×（111.1000...000(n个1n个0)-2×11...1(n个)）
=4×111.1 (n个)44...44(2n个)-88...88(n个) =4×（111.....1(2n个)-2×11...1(n个)）=4×（111.....1000...000(n个1n个0)-2×11...1(n个)）=4×111....1 (n个)×（1000...0 (n个)-2）=4×111....1 (n个)×99....9(n个)=36×111....1 (n个)×111....1 (n个)=6²×111....1 (n个)²=66....6²