2004*2005-1分之2004+2005*2003

2004×2005-1分之2004+2005×2003
=【2004+(2004+1)(2004-1)】÷(2004×2005-1)
=(2004+2004×2004-1)÷(2004×2005-1)
=(2004×2005-1)÷(2004×2005-1)
=4018019÷4018019
=1

分子= 2004+2005*2003
=2004+2005*(2004-1)
=2004+2005*2004-2005
=2004*2005-1=分母
所以原式=1

2004*2005-1分之2004+2005*2003
=(2004+(2004+1)(2004-1))/(2004*2005-1)
=(2004+2004*2004-1)/(2004*2005-1)
=(2004*2005-1)/(2004*2005-1)
=1

2004*2005-1
=2004*（2004+1）-1
=2004^2+2003
2004+2005*2003
=2004+(2004+1)*(2004-1)
=2004+2004^2-1
=2003+2004^2
所以 (2004+2005*2003)/(2004*2005-1)=1