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关于数学计算(按规律)
1X2=3/1 X1X2X3
1X2+2X3=3/1 X2X3X4
1X2+2X3+3X4=3/1 X3X4X5
1X2+2X3+3X4+4X5=3/1 X4X5X6
……
(1)用带N的式子表示你发现的规律;
(2)计算:1X2+2X3+3X4+……+100X(100+1).
人气:168 ℃ 时间:2020-01-26 08:28:27
解答
1X2+2X3+3X4+……+n(n+1)=n(n+1)(n+2)/3
1X2+2X3+3X4+……+100X(100+1)
=100*101*102/3
=343400
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