等差数列{An}和{Bn},A1=25,B1=75,A100加B100=100,则数列{An加Bn}前一百项和为多少?怎么算

问题描述:

等差数列{An}和{Bn},A1=25,B1=75,A100加B100=100,则数列{An加Bn}前一百项和为多少?怎么算

An加Bn也是等差数列
SAn+Bn=100(a1+b1+a100+b100)/2=100(25+75+100)/2=10000