计算 1/2+3/4+7/8+15/16+31/32+63/64+127/128+255/256

题目

计算 1/2+3/4+7/8+15/16+31/32+63/64+127/128+255/256

答案

1/2+3/4+7/8+15/16+31/32+63/64+127/128+255/256
=（1-1/2)+(1-1/4)+(1-1/8)+(1-1/16)+(1-1/32)+(1-1/64)+(1-1/128)+(1-1/256)
=1*8-(1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256)
=8-(1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/256)+1/256
=8-(1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/128)+1/256
=8-(1/2+1/4+1/8+1/16+1/32+1/64+1/64)+1/256
=8-(1/2+1/4+1/8+1/16+1/32+1/32)+1/256
=8-(1/2+1/4+1/8+1/16+1/16)+1/256
=8-(1/2+1/4+1/8+1/8)+1/256
=8-(1/2+1/4+1/4)+1/256
=8-(1/2+1/2)+1/256
=8-1+1/256
=7+1/256
所以,结果为：
七又二百五十六分之一
轻松一下!