等差数列中a1,d,等比中a1,q的限制?如：等比中a1不等于0

等差数列中a1,d,等比中a1,q的限制?如：等比中a1不等于0 在等差数列an中,公差D不等于0,a1.a2 .a4成等比,求q解出a1=d,之后怎么算? 等差数列{an}中,公差d不等于0.a2是a1和a4的等比中项,已知数列a1,a3,ak1,ak2.akn成等比数列,求数 11、设等差数列{an}的公差d≠0,a1=4d,若ak是a1与a6的等比中项,则k的值为 7、设等差数列{an}的公差d≠0,a1=4d,若ak是a1与a6的等比中项,则k的值为 设等差数列{an}公差d≠0 a1=4d,若ak是a1与a2k的等比中项,则k的值为 设等差数列｛an｝的公差d≠0,a1=9d,若ak是a1与a2k的等比中项,则k= 设等差数列｛an｝的公差为d不为0,a1＝9d,若ak是a1与a2k的等比中项,则k＝ 设等差数列{An}的公差d不为0,A1=9d.若Ak是A1与A2k的等比中项,则k等于几 等差数列{An}的公差d不等于0,A1＝9d,Ak是A1与A2k的等比中项,则k＝? 设等差数列{an}的公差d不为0,a1=9d,若ak是a1与a2k的等比中项,则k=? 设等差数列{an}的公差d不为0,a1=9d.若ak是a1与a2k的等比中项,则k=? 设等差数列an的公差d不为0,a1=9d.若ak是a1与a2k的等比中项,则k等于多少? 设等差数列{an}公差d不为0,a1=9d,若ak是a1和a2k的等比中项,则k=______ 已知等差数列an中,a1=8,且a5是a1和a7的等比中项,则S10 等差数列前六项和为60,a6为a1和a21的等比中项.求通项公式 等差数列中,a1 等差数列{An}中,a1