{an}为等比数列,若a1+a2+a3=26,a4-a1=52,求an
{an}为等比数列,若a1+a2+a3=26,a4-a1=52,求an
{an}是等比数列若a1+a2+a3=26 ,a4-a1=52,求an
等差数列an的公差为d=2,若a1,a3,a4成等比数列,求a2.
已知数列{an}为等比数列 a1+a2=3 a3+a4=12 求an S4
已知数列{An}为等比数列,若A1+A2+A3=7,A1*A2*A3=8,求An
若{an}为等比数列,a1+a2=3,a3+a4=6,则S8等于?
已知等差数列{an}的公差为3,若a1,a3,a4成等比数列,则a2=
已知等差数列{an}的公差为2,若a1,a3,a4成等比数列,则a2=?
等差数列{an}中公比为3,若a1,a3,a4成等比数列,则a2=?
等差数列an ,的公差为3,若a1,a3,a4成等比数列,则a2=?
若等比数列{an}满足a1+a2=3,a3+a4=12,则a1+a2+a3+……+an=
急阿.已知An为等比数列,当a1*a3=36,a2+a4=60,求a1和q.