傻逼不要来10*(1/11)+11*(1/12)+.+19*(1/20)何解?10*(1/11)+11*(1/12)+。+19*(1/20)跟1/(10*11)+1*(11*12)+。+1/(19*20)完全不同,脑残还真多
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傻逼不要来10*(1/11)+11*(1/12)+.+19*(1/20)何解?10*(1/11)+11*(1/12)+。+19*(1/20)跟1/(10*11)+1*(11*12)+。+1/(19*20)完全不同,脑残还真多
傻逼不要来
10*(1/11)+11*(1/12)+.+19*(1/20)何解?
10*(1/11)+11*(1/12)+。+19*(1/20)跟1/(10*11)+1*(11*12)+。+1/(19*20)完全不同,脑残还真多
傻逼不要来10*(1/11)+11*(1/12)+.+19*(1/20)何解?10*(1/11)+11*(1/12)+。+19*(1/20)跟1/(10*11)+1*(11*12)+。+1/(19*20)完全不同,脑残还真多
等于100/11,约等于9.09……
先把10/11化成1/(1+1/10),然后把1/(1+1/10)化成10*(1-1/(1+1/10)),依此类推加到19/20
再把1/(1+1/10)乘以十倍再加上10*(1-1/(1+1/10)),有10*(1-1/(1+1/10))=1/(1+1/10)
所以11倍整体就等于100,答案为100/11
假设n=10,n/n+1+n+1/n+2+...n+10/n+11=11n+55/11n+66=165/176
10乘以11分之1+11乘以12分之1+12乘以13分之1+……+19乘以20分之1 =1/10-1/11+1/11-1/12+1/12-1/13+-----+1/19-1/20 =1/10-1/20 =1/20
原式=1-1/11+1-1/12+。。。+1-1/20
=10-(1/11+1/12+1/13+1/14+1/15+1/16+1/17+1/18+1/19+1/20)
=10-(1/11+1/3-1/4+1/13+1/10-1/35+1/6-1/10+1/12-1/48+1/17+1/14-1/63+1/19+1/4-1/5)
=10-(1/11+1/3+1...
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原式=1-1/11+1-1/12+。。。+1-1/20
=10-(1/11+1/12+1/13+1/14+1/15+1/16+1/17+1/18+1/19+1/20)
=10-(1/11+1/3-1/4+1/13+1/10-1/35+1/6-1/10+1/12-1/48+1/17+1/14-1/63+1/19+1/4-1/5)
=10-(1/11+1/3+1/13-1/35+1/6+1/12-1/48+1/17+1/14-1/63+1/19-1/5)
=10-(1/11+1/3+1/13+1/14-1/10+1/6+1/12+1/16-1/12+1/17+1/14+1/18-1/14+1/19-1/5)
=10-(1/11+1/3+1/13+1/14-1/10+1/6+1/16+1/17+1/18+1/19-1/5)
以此类推,最终可得结果。
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10乘以11分之1+11乘以12分之1+12乘以13分之1+……+19乘以20分之1
=1/10-1/11+1/11-1/12+1/12-1/13+-----+1/19-1/20
=1/10-1/20
=1/20
以上答案仅供参考!!