1+2+3+4+5+6+7+8+9+10+11+12....................................1000000
2007-05-16 04:48:59 · 9 個解答 · 發問者 Karen 2 in 科學 ➔ 數學
您好!
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問題:1+2+3+4+5+6+7+8+9+10+11+12....................................1000000=?
回答:
只要你知道計算方法,其實好易計:
♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀♀
方法1:
你這一個數,是三角形數。
三角形數計算公式:
nx(n+1)
-------
2
n是那個三角形數最大的數字,在這裏是1000000(一百萬……汗呀)。
根據上列公式,計算方法如下(挻煩的):
1000000x(1000000+1)
-------------------
2
1000000x1000001
=---------------
2
1000001000000
=------------- (無顏……)
2
=500000500000 (極大~~)
============
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當然,不只一種方法--
方法2:
這類形的數有另一種計算方法:
(a+b)×(b÷2)
*a是該數最小的數--這裏是1。
b是該數最大的數--這裏是999。
根據上列公式,計算方法如下:
(1+1000000)×(1000000÷2)
=1000001x500000
=500000500000
============
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方法3:(最「低B」的做法,不過我小時也是用這方法+很多人用的方法):
有點類似整0:
1000000----
1+999999
2+999998
3+999997
4+999996
5+999995
6+999994
7+999993
8+999992
9+999991
10+999990
11+999989
12+999988
13+999987
仲要寫好多好多………………
499997+500003
499998+500002
499999+500001
500000----
看着上面的「表」,知道有500000個1000000和1個500000
即:
(500000x1000000)+500000
=500000000000+500000
=500000500000
============
★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
最後,總結一下答案:500000500000
是嗎?
2007-05-16 18:55:27 補充:
有關方法2:方法好像與方法1類似,又不一樣,又好像有點問題……a應是1……不是最少的數,如是最少的數:40+41+42+43+44+45即變成了:(40+45)x45÷2=85x22.5=1912.5!? * * ﹏所以方法2是有問題的……= = 3
2007-05-17 21:00:11 補充:
……
2007-05-16 09:47:59 · answer #1 · answered by ? 4 · 0⤊ 0⤋
*****!
2007-05-17 14:03:00 · answer #2 · answered by ShikaP 7 · 0⤊ 0⤋
(1+100000)x100000/2
=100001x50000
=5000050000
2007-05-17 09:11:15 · answer #3 · answered by Kui Yat 3 · 0⤊ 0⤋
=(1+2+3+4+5+6+7+8+9+10+10+12=78)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+(13+14+15+16+17+18+19+20+21+22=175)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+(23+24+25+26+27+28+29+30+31+32=275)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+(33+34+35+36+37+38+39+40+41+42=375)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+{(78+175+275+375=)903+1000000}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
={(903+.......1001=8343)+
2007-05-16 22:08:33 補充:
=(903+.........1000000)= 500000500000=].......^^^^^^^^^
2007-05-16 18:05:01 · answer #4 · answered by Cindy 2 · 0⤊ 0⤋
(1+1000000)x100000/2
=(1+1000000)x500000
=1000001x500000
=500000500000
2007-05-16 15:11:45 · answer #5 · answered by ka man 2 · 0⤊ 0⤋
(1+1000000)x500000
=1000001x500000
=500000500000
2007-05-16 10:24:11 補充:
http://www.hkedcity.net/resources/ires/ires_browse.phtml?type=list&res_cat_id=5825see 小高斯說數型【字幕版】
2007-05-16 06:11:26 · answer #6 · answered by 羯瑜 2 · 0⤊ 0⤋
(1+1000000)*1000000/2
=1000001*500000
=500000500000
2007-05-16 05:03:39 · answer #7 · answered by Anthony 4 · 0⤊ 0⤋
1+2+3+4+5......+100000
=100000X100001/2
=5000050000
2007-05-16 04:56:23 · answer #8 · answered by waiting 6 · 0⤊ 0⤋
1+2+3+.....+1000000=(1+1000000)X1000000/2=500000500000
2007-05-16 04:54:27 · answer #9 · answered by Anonymous · 0⤊ 0⤋