3/2×5+3/5×8+3/8×11+…+3/1997×2000+3/2000×2003= _ .
问题描述:
+3 2×5
+3 5×8
+…+3 8×11
+3 1997×2000
= ___ .3 2000×2003
答
+3 2×5
+3 5×8
+…+3 8×11
+3 1997×2000
,3 2000×2003
=
-1 2
+1 5
-1 5
+1 8
-1 8
+…+1 11
-1 1997
+1 2000
-1 2000
,1 2003
=
-1 2
,1 2003
=
.2001 4006
故答案为:
.2001 4006