观察下面算式,你发现了什么? 1/2=1/1×2=1-1/2 1/6=1/2×3=1/2-1/3 1/12=1/3×4=1/3-1/4 请你计算. 1/2+1/6+1/12+1/20+1/30+1/42+1/56=
问题描述:
观察下面算式,你发现了什么?
=1 2
=1-1 1×2
1 2
=1 6
=1 2×3
-1 2
1 3
=1 12
=1 3×4
-1 3
1 4
请你计算.
+1 2
+1 6
+1 12
+1 20
+1 30
+1 42
= 1 56
答
+1 2
+1 6
+1 12
+1 20
+1 30
+1 42
1 56
=1-
+1 2
-1 2
+1 3
-1 3
+1 4
-1 4
+1 5
-1 5
+1 6
-1 6
+1 7
-1 7
1 8
=1-
1 8
=
.7 8