已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+.+1/(a+2012)

问题描述:

已知|ab-2|与|b-1|互为相反数,试求代数式1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+.+1/(a+2012)
1/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+.+1/(a+2012)(b+2012)

|ab-2|+|b-1|=0b-1=0 b=1ab=2 a=2/b=21/ab+1/(a+1)(b+1)+1/(a+2)(b+2)+.+1/(a+2012)(b+2012)=1/1x2+1/2x3+1/3x4+...+1/2013x2014=1-1/2+1/2-1/3+1/3-1/4+...+1/2013-1/2014=1-1/2014=2013/2014