已知数列｛an｝是等比数列,m,n,p∈N﹡,且m,n,p成等差数列,求证：am,an,ap依次
问题描述：
已知数列｛an｝是等比数列,m,n,p∈N﹡,且m,n,p成等差数列,求证：am,an,ap依次
答
2n = m + p
am * q / a1 = q^m
an * q / a1 = q^n
ap * q / a1 = q^p
q^m * q^p = q^n * q^n
am * ap = an ^ 2