第1个回答 2012-01-17
1+1/2+1/4+1/8+1/16+1/32+1/64
=1+1/2+1/4+1/8+1/16+1/32+1/64+1/64 - 1/64
=1+1/2+1/4+1/8+1/16+1/32+1/32 - 1/64
=1+1/2+1/4+1/8+1/16+1/16- 1/64
=1+1/2+1/4+1/8+1/8 - 1/64
=1+1/2+1/4+1/4 - 1/64
=1+1/2+1/2 - 1/64
=2-1/64;
8*(1+1/2+1/4+1/8+1/16+1/32+1/64)=16-1/8=127/8