(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)

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(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)

(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)
(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)

(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)
变形为:(-2007/2008)*(-2006/2007)*(-2005/2006)*.*(-2/3)*(-1/2)=-1/2008
把括号里的变一下就可约分了,自己拿笔划下.
楼下的大哥2007个好不!

(1/2008-1)*(1/2007-1)*(1/2006-1)*...*(1/3-1)*(1/2-1)
=(-2007/2008)*(-2006/2007)*(-2005/2006)*…*(-2/3)*(-1/2)
然后约分……自己拿笔画画看……
=1/2008【总共有2008个分数,所以得正数(负负得正嘛~~)】