=1+1/2+1/4+1/8+1/16+1/32+1/64+1/126+1/256+.1/2 ^100
=1+(2^100-1)/2^100确定？过程详细点1+1/2+1/4+1/8+1/16+1/32+1/64
通分
=1+32/64+16/64+8/64+4/64+2/64+1/64
=1+(31+16+8+4+2+1)/64
=1+63/64
=1+(64-1)/64
明白了吧