2006/(2006*2006-2007*2005)+2006÷(2006又2006/2007)
=2006/[2006²-(2006+1)(2006-1)]+2006/(2006+2006/2007)
=2006/(2006²-2006²+1)+1/(1+1/2007)
=2006+1/(2008/2007)
=2006+2007/2008
=2006又2007/2008
2006/(2006*2006-2007*2005)+2006÷(2006又2006/2007)
=2006/[2006²-(2006+1)(2006-1)]+2006/(2006+2006/2007)
=2006/(2006²-2006²+1)+1/(1+1/2007)
=2006+1/(2008/2007)
=2006+2007/2008
=2006又2007/2008