3/2+5/4+9/8+17/16+…+257/256.
问题描述:
+3 2
+5 4
+9 8
+…+17 16
. 257 256
答
+3 2
+5 4
+9 8
+…+17 16
,257 256
=1+
+1+1 2
+1+1 4
+1+1 8
+…+1+1 16
,1 256
=(1+1+1+1+…+1)+(
+1 2
+1 4
+1 8
+…+1 16
),1 256
=8+(1-
+1 2
-1 2
+1 4
-1 4
+1 8
-1 8
+…+1 16
-1 128
),1 256
=8+(1-
),1 256
=8+
,255 256
=8
.255 256