|a+b|+|a+1|=0 计算1/(a-1)(b+1)+/1/(a-2)(b+2)+........+1/(a-2007)(b+2007)

来源:百度知道 编辑:UC知道 时间:2024/05/29 20:22:15
|a-1|+(b-2)的2次方=0 计算1/ab + 1/(a+1)(b+1) + 1/(a+2)(b+2) +...+ 1/(a+2007)(b+2007) 的值
题目不用解

|a+b|+|a+1|=0 计算1/(a-1)(b+1)+/1/(a-2)(b+2)+........+1/(a-2007)(b+2007)
解有题意知道a+b=0 a+1=0
a=-1 b=1
1/(a-1)(b+1)+/1/(a-2)(b+2)+........+1/(a-2007)(b+2007)
=-1/4-1/9-1/16???????

|a-1|+(b-2)的2次方=0 计算1/ab + 1/(a+1)(b+1) + 1/(a+2)(b+2) +...+ 1/(a+2007)(b+2007) 的值
解:a=1| b=2
1/ab + 1/(a+1)(b+1) + 1/(a+2)(b+2) +...+ 1/(a+2007)(b+2007)
=1/2+1/6+。。。。+1/2008*2009
=1-1/2+1/2-1/3+1/3-1/4......+1/2008-1/2009
=1-1/2009
=2008/2009