等差数列前三项为x-1,x+1,2x+3,则x=
问题描述:
等差数列前三项为x-1,x+1,2x+3,则x=
答
2(x+1)=x-1+2x+3
x=-1
等差数列前三项为x-1,x+1,2x+3,则x=
2(x+1)=x-1+2x+3
x=-1