从后往前算,两个1/32加起来是1/16,再两个1/16加起来是1/8,。。。。
最后答案是1.
从后向前算
=1/32+1/32+1/16+1/8+1/4+1/2
=1/16+1/16+1/8+。。。
=1/8+1/8+1/4+。。。
=1/4+1/4+1/2
=1/2+1/2
=1
补充回答:等比数列(相加)。
1/2+1/4+1/8+1/16+1/32+1/32用简便方法计算:传从后面往前加,结果=1
等比数列,公比=1/2
1)
Sn=1/2+1/4+1/8+1/16+1/32+1/32+...+1/2^n
=1-1/2^n
32=2^5,n=5
S5=1-1/32=31/32
2)
=1/32+1/32+1/16+1/8+1/4+1/2-1/32
=1/16+1/16+1/8+。。。
=1/8+1/8+1/4+。。。
=1/4+1/4+1/2-1/32
=1/2+1/2-1/32
=1-1/32
=31/32