等差数列{an}满足a1+a2+a3+…a101=0,则有
问题描述:
等差数列{an}满足a1+a2+a3+…a101=0,则有
答
a101=a100+d=a99+2d=```=a1+100d
a1+a2+a3+…a101=a1+(a1+d)+(a1+2d)+```(a1+100d)=101a1+5050d=0
a1+50d=0
a1=-50d
即a51=0