几道中学数学题,☆答对加10分一道☆(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)已知|a|=-a,b
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/04 03:26:32
![几道中学数学题,☆答对加10分一道☆(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)已知|a|=-a,b](/uploads/image/z/6110883-27-3.jpg?t=%E5%87%A0%E9%81%93%E4%B8%AD%E5%AD%A6%E6%95%B0%E5%AD%A6%E9%A2%98%2C%E2%98%86%E7%AD%94%E5%AF%B9%E5%8A%A010%E5%88%86%E4%B8%80%E9%81%93%E2%98%86%281%2B1%2F1997%2B1%2F1999%2B1%2F2001%29%2A%281%2F1997%2B1%2F1999%2B1%2F2001%2B1%2F2003%29-%281%2B1%2F1997%2B1%2F1999%2B1%2F2001%2B1%2F2003%29%2A%281%2F1997%2B1%2F1999%2B1%2F2001%29%E5%B7%B2%E7%9F%A5%7Ca%7C%3D-a%2Cb)
几道中学数学题,☆答对加10分一道☆(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)已知|a|=-a,b
几道中学数学题,☆答对加10分一道☆
(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)
已知|a|=-a,b
几道中学数学题,☆答对加10分一道☆(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)已知|a|=-a,b
1、
(1+1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1+1/1997+1/1999+1/2001+1/2003)*(1/1997+1/1999+1/2001)
用乘法分配率
=[(1/1997+1/1999+1/2001+1/2003)+(1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)]-[(1/1997+1/1999+1/2001)+(1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)]
=(1/1997+1/1999+1/2001+1/2003)+(1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)-(1/1997+1/1999+1/2001)-(1/1997+1/1999+1/2001)*(1/1997+1/1999+1/2001+1/2003)
=(1/1997+1/1999+1/2001+1/2003)-(1/1997+1/1999+1/2001)
=1/1997+1/1999+1/2001+1/2003-1/1997-1/1999-1/2001
=1/2003
2、因为|a|=-a,所以a≤0,又b