第2个回答 2018-06-16
2/3
= 1/2 + 1/6
=2^(-1) + 2^(-3) + 1/6 -1/8
=2^(-1) + 2^(-3) + 1/24
=2^(-1) + 2^(-3) + 2^(-5) + 1/24 -1/32
=2^(-1) + 2^(-3) + 2^(-5) + 1/96
=2^(-1) + 2^(-3) + 2^(-5) +2^(-7)+ 1/96-1/128
=2^(-1) + 2^(-3) + 2^(-5) +2^(-7)+ 1/384
=2^(-1) + 2^(-3) + 2^(-5) +2^(-7)+ 2^(-9)+ 1/384 -1/512
=...
=0.101010....(b)本回答被网友采纳