来自李长征的问题
(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回答
2020-03-24 12:57
(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!