Question

若a不等于b,a、X1、X2、b和a1、y1、y2、y3、b都是等差数列,求（x2-x1)/(y2-y1).

Answer 1

X1=a+(b-a)/3

X2=a+2(b-a)/3

X2-X1=(b-a)/3

Y1=a+(b-a)/4

Y2=a+2(b-a)/4

Y3=a+3(b-a)/4

Y2-Y1=(b-a)/4

所以(X2-X1)/(Y2-Y1)=4/3