1*4/3+4*7/3+7*10/3+.2008*2011/3 简便算法(50/1-1)(49/1-1)(48/1-1)......(4/1-1)(3/1-1)(2/1-1)

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1*4/3+4*7/3+7*10/3+.2008*2011/3 简便算法(50/1-1)(49/1-1)(48/1-1)......(4/1-1)(3/1-1)(2/1-1)

1*4/3+4*7/3+7*10/3+.2008*2011/3 简便算法(50/1-1)(49/1-1)(48/1-1)......(4/1-1)(3/1-1)(2/1-1)
1*4/3+4*7/3+7*10/3+.2008*2011/3 简便算法
(50/1-1)(49/1-1)(48/1-1)......(4/1-1)(3/1-1)(2/1-1)

1*4/3+4*7/3+7*10/3+.2008*2011/3 简便算法(50/1-1)(49/1-1)(48/1-1)......(4/1-1)(3/1-1)(2/1-1)
原式=1-4/1+4/1-7/1+……+2008/1-2011/1
=1-2011/1
=2011/2010

看着好不习惯……
原式=1/2×2/3×3/4×……×49/50
=1/50
我跟你的是反着的啊

1*4/3+4*7/3+7*10/3+.....2008*2011/3
=1-1/4+1/4-1/7+...+1/2008-1/2011
=1-1/2011

是不是分子和分母打错位置了?
3/(1*4)+3/(4*7)+3/(7*10)+……+3/(2008*2011)
=1-1/4+1/4-1/7+1/7-1/10+……+1/2008-1/2011
=1-1/2011
=2010/2011.
(1/50-1)(1/49-1)(1/48-1)......(1/4-1)(1/3-1)(1/2-1)
=(-4...

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是不是分子和分母打错位置了?
3/(1*4)+3/(4*7)+3/(7*10)+……+3/(2008*2011)
=1-1/4+1/4-1/7+1/7-1/10+……+1/2008-1/2011
=1-1/2011
=2010/2011.
(1/50-1)(1/49-1)(1/48-1)......(1/4-1)(1/3-1)(1/2-1)
=(-49/50)(-48/49)(-47/48)……(-3/4)(-2/3)(-1/2)
=-1/50

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