原式=1/（1*2）+1/（2*3）+1/（3*4）.+1/（9*10）
=1-1/2+1/2-1/3+1/3.+1/9-1/10
=1-1/10
=9/10
数学大师快来1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90要规律求求啦
1个回答
相关问题
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数学探索规律2/1+6/1+12/1+20/1+30/1+42/1+56/1+72/1+90/1=?
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2\1-6\1-12\1-20\1-30\1-42\1-56\1-72\1-90\1
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1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=
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2/1＋6/1＋12/1＋20/1＋30/1＋42/1＋56/1＋72/1＋90/1
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1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
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1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=?
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(1)2/1+6/1+12/1+20/1+30/1+42/1+56/1+72/1+90/1
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计算：1/2+1/6+1/12+1/20+/+1/30+1/42+1/56+1/72+1/90
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计算1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
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1/12+1/20+1/30+1/42+1/56+1/72+1/90=?