已知a,x1,x2,x3,b成等差数列,a,y1,y2,y3,b成等比数列,a<b<0,则x3-x3/y2=

问题描述:

已知a,x1,x2,x3,b成等差数列,a,y1,y2,y3,b成等比数列,a<b<0,则x3-x3/y2=

x3-a=3d
b-a=4d
∴(x3-a)/(b-a)=3/4
x3=¾b+¼a
y2²=ab
y2=(ab)^½
原式=¾b+¼a-¾(a/b)^½-¼(b/a)^½