2001×2003/2002+2002×2004/2003+4005/(2002×2003)

2001×2003/2002 + 2002×2004/2003 + 4005/(2002×2003)=(2002-1)(2002+1)/2002 + (2003-1)(2003+1)/2003 + (2×2002+1)/(2002×2003)=(2002²-1)/2002 + (2003²-1)/2003 + (2×2002+1)*[1/2002 - 1/2003)...答案是4005.2001×2003/2002 + 2002×2004/2003 + 4005/(2002×2003) =(2002-1)(2002+1)/2002 + (2003-1)(2003+1)/2003 + (2×2002+1)/(2002×2003) =(2002²-1)/2002 + (2003²-1)/2003 + (2×2002+1)*[1/2002 - 1/2003) =2002²/2002 - 1/2002 + 2003²/2003 - 1/2003 + 2 -2×2002/2003+1/2002-1/2003 =2002-1/2002+2003-1/2003+2-(2-2/2003)+1/2002-1/2003 =4005-1/2002-1/2003+2/2003+1/2002-1/2003 =4005呃……我说过不要贴别人的。不看拉倒，心情不好……