摘要:2.探究过程:观察下列各式及其验证过程. (1)2= 验证:2=×== == (2)3= 验证:3=×== == 同理可得:4 5.-- 通过上述探究你能猜测出: a= ,并验证你的结论.
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观察下列各等式,并回答问题:
=1-
;
=
-
;
=
-
;
=
-
;…
(1)填空:
= (n是整数);
(2)计算:
+
+
+
+…+
.
解:原式=(1-
)+(
-
)+(
-
)+…+(
-
)=1-
+
-
+
-
+…+
-
=1-
=
请同学们观察上面解题过程后计算:
+
+
+
+…+
.
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| 1 |
| 1×2 |
| 1 |
| 2 |
| 1 |
| 2×3 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 3×4 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 4×5 |
| 1 |
| 4 |
| 1 |
| 5 |
(1)填空:
| 1 |
| n(n+1) |
(2)计算:
| 1 |
| 1×2 |
| 1 |
| 2×3 |
| 1 |
| 3×4 |
| 1 |
| 4×5 |
| 1 |
| 8×9 |
解:原式=(1-
| 1 |
| 2 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 8 |
| 1 |
| 9 |
| 1 |
| 2 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 8 |
| 1 |
| 9 |
| 1 |
| 9 |
| 8 |
| 9 |
请同学们观察上面解题过程后计算:
| 1 |
| 1×2 |
| 1 |
| 2×3 |
| 1 |
| 3×4 |
| 1 |
| 4×5 |
| 1 |
| 2009×2010 |
观察下列各正方形图案,每条边上有n(n≥2)个圆点,每个图案中圆点的总数是S.

(1)数一数如n=2时,s=4:则当n=3时,s=
(2)你能不能推断出当n=10时,s的值?(要求写出解题过程)
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(1)数一数如n=2时,s=4:则当n=3时,s=
8
8
,当n=4时,s=12
12
.(2)你能不能推断出当n=10时,s的值?(要求写出解题过程)