1/2+1/6+1/12+1/20+1/30+1/42+1/56=?5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=?(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=?今年延边教育出版社出版的,在第27页 本人大学在校,这种题高中应该做过,
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/21 06:52:29
![1/2+1/6+1/12+1/20+1/30+1/42+1/56=?5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=?(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=?今年延边教育出版社出版的,在第27页 本人大学在校,这种题高中应该做过,](/uploads/image/z/1049725-37-5.jpg?t=1%2F2%2B1%2F6%2B1%2F12%2B1%2F20%2B1%2F30%2B1%2F42%2B1%2F56%3D%3F5%2F%EF%BC%881%2B6%EF%BC%89%2B5%2F%EF%BC%886%2B11%EF%BC%89%2B5%2F%EF%BC%8811%2B16%EF%BC%89%2B%E2%80%A6%E2%80%A6%2B5%2F%EF%BC%8876%2B81%EF%BC%89%3D%3F%EF%BC%881%2B2%2B3%2B4%2B5%2B6%2B7%2B6%2B5%2B4%2B3%2B2%2B1%EF%BC%89%2F%EF%BC%88777777%2A777777%EF%BC%89%3D%3F%E4%BB%8A%E5%B9%B4%E5%BB%B6%E8%BE%B9%E6%95%99%E8%82%B2%E5%87%BA%E7%89%88%E7%A4%BE%E5%87%BA%E7%89%88%E7%9A%84%EF%BC%8C%E5%9C%A8%E7%AC%AC27%E9%A1%B5+%E6%9C%AC%E4%BA%BA%E5%A4%A7%E5%AD%A6%E5%9C%A8%E6%A0%A1%EF%BC%8C%E8%BF%99%E7%A7%8D%E9%A2%98%E9%AB%98%E4%B8%AD%E5%BA%94%E8%AF%A5%E5%81%9A%E8%BF%87%EF%BC%8C)
1/2+1/6+1/12+1/20+1/30+1/42+1/56=?5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=?(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=?今年延边教育出版社出版的,在第27页 本人大学在校,这种题高中应该做过,
1/2+1/6+1/12+1/20+1/30+1/42+1/56=?
5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=?
(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=?
今年延边教育出版社出版的,在第27页
本人大学在校,这种题高中应该做过,可是早忘了,实在影响大学生在小表妹心中的形象了!
1/2+1/6+1/12+1/20+1/30+1/42+1/56=?5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=?(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=?今年延边教育出版社出版的,在第27页 本人大学在校,这种题高中应该做过,
(1).1/2+1/6+1/12+1/20+1/30+1/42+1/56
=1/2+1/2*1/3+1/3*1/4+...+1/7*1/8
=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)
=1/2+1/2-1/8
=7/8
(2).5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)
是不是你抄错了
5/(1*6)+5/(6*11)+5/(11*16)+……+5/(76*81)
=1-1/6+1/6-1/11+...+1/76-1/81
=1-1/81
=80/81
方法同上.
(3).(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)
=7*7/(777777*777777)
=1*1/(111111*111111)
=1/(111111*111111)
11*11=121
111*111=12321
1111*1111=1234321
...
111111*111111=12345654321
(1)=1-1/2+1/2-1/3+1/3......+1/7-1/8=7/8
分解为1-1/2+(1/2-1/3)+(1/3-1/4)......+(1/7-1/8)
裂解再抵消。
(2)规律是5/7+5/17+5/27+......5/157有规律不过我也不会
(3)=[(1+6)*3*2+7]/777777*777777
=7*7/777777*777...
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(1)=1-1/2+1/2-1/3+1/3......+1/7-1/8=7/8
分解为1-1/2+(1/2-1/3)+(1/3-1/4)......+(1/7-1/8)
裂解再抵消。
(2)规律是5/7+5/17+5/27+......5/157有规律不过我也不会
(3)=[(1+6)*3*2+7]/777777*777777
=7*7/777777*777777
=1*1/111111*111111
=1/12345654321
(1+2+3+4+5+6+7+6+5+4+3+2+1)=49=7*7
7*7/777777*777777=1*1/111111*111111
回文数,先举例1*1=1
11*11=121
111*111=12321
所以1*1/111111*111111=1/12345654321
我回答的最全采纳啊啊啊啊啊啊啊啊啊啊啊!!!!!!!!!!!!!!!!!!!!!!!!!
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1/2+1/6+1/12+1/20+1/30+1/42+1/56=18
5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=218/6
(1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=218/68
1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=22218
一·原式=(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)=1-1/2+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
二·原式=
1/2+1/6+1/12+1/20+1/30+1/42+1/56 因为1/1*2 + 1/2*3 + 1/3*4 + 1/4*5 + 1/5*6 + 1/6*7 + 1/7*8 =1/8 ,再用1/8乘以7,得7/8
楼主太搞笑了!!
①=1/(1×2)+1/(2×3)+1/(3×4)+…+1/(6×7)+1/(7×8)
=1-1/2+1/2-1/3+1/3-1/4+…+1/6-1/7+1/7-1/8
=7/8
②=5×[1/(2+5×1)+1/(2+5×3)+1/(2+5×5)+…+1/(2+5×31)]
然后通分,接着可以代掉,过程太麻烦了,故你自己去算
③=[(1+6)+...
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①=1/(1×2)+1/(2×3)+1/(3×4)+…+1/(6×7)+1/(7×8)
=1-1/2+1/2-1/3+1/3-1/4+…+1/6-1/7+1/7-1/8
=7/8
②=5×[1/(2+5×1)+1/(2+5×3)+1/(2+5×5)+…+1/(2+5×31)]
然后通分,接着可以代掉,过程太麻烦了,故你自己去算
③=[(1+6)+(2+5)+(3+4)+…+(4+3)(5+2)(6+1)]/[(7×7)×(111111 ×111111)
=(7×7)/[(7×7)×(111111×111111)]
=1/(111111×111111)
=1/12345654321
我回答的更全采纳啊!!!!!!!!!!!!!!
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I don't know.
/2+1/6+1/12+1/20+1/30+1/42+1/56
=1/(1*2)+1/(2*3)+1/(3*4)+1/(4*5)+1/(5*6)+1/(6*7)+1/(7*8)
=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
(5/1×6+4/6×11+5/11×6+…+5/76×81)/(5/4)=(1-1/6+1/6-1/11+1/11…+1/76-1/81)/(5/4)=(1-1/81)*(4/5)=64/81
不会
(1).1/2+1/6+1/12+1/20+1/30+1/42+1/56=1-1/2+1/2-1/3+1/3......+1/7-1/8=7/8
(2) .5/(1+6)+5/(6+11)+5/(11+16)+……+5/(76+81)=2
(3). (1+2+3+4+5+6+7+6+5+4+3+2+1)/(777777*777777)=0.000000000081000162000243
1/2+1/6+1/12+1/20+1/30+1/42+1/56=7/8
天啊,我是高级工程师啊,居然都不会。虽然当年数学差了点,但也不至于差这么多啊!!!!!现在的孩子怎么活啊???????