2004.5*1997.5-2001.5*1999.5=?ji ji ji

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/28 03:53:23
2004.5*1997.5-2001.5*1999.5=?ji ji ji
xP 0]%9Ǘ 0 tP 8HYϱ`xݻow1biۮ;~=ߝy5*4JmqXx 3h00Q\ rx*$EW<\脤fF/??C/s5DU(A6 B804f

2004.5*1997.5-2001.5*1999.5=?ji ji ji
2004.5*1997.5-2001.5*1999.5=?
ji ji ji

2004.5*1997.5-2001.5*1999.5=?ji ji ji
2004.5*1997.5-2001.5*1999.5
=(2001+3.5)(2001-3.5)-(2000.5+1)(2000.5-1)
=2001*2001-3.5*3.5-2000.5*2000.5+1
=(2001+2000.5)(2001-2000.5)-12.25+1
=4001.5*0.5-11.25
=2000.75-11.25
=1989.5

等于1989.5

2004.5*1997.5-2001.5*1999.5
= (2000 + 4.5)(2000-2.5) - (2000+1.5)(2000-0.5)
=4000000 - 5000 + 9000 - 4,5*2.5 - 4000000 + 1000 - 3000 + 1.5*0.5
= 2000 -10.5
= 1989.5