已知{An}为等差数列,且A7-2A4=-1,A3=0,则公差d=?
已知{An}为等差数列,且A7-2A4=-1,A3=0,则公差d=?
等差数列{an},a7-2a4=-1,且a3=0,则公差d=( )
己知{an}为等差数列,且a7-2a4=-1,a3=0,则公差d=______.2、已知Sn=1/3(an-1),
已知等差数列{an}的公差为正数,且a3×a7=-12,a4+a6=-4,则S20为() A.180 B.-180 C.
若等差数列a1,a2,a3,...,an,...的公差为d,则数列a1,a4,a7,...,a3n-2,...公差为
已知等差数列{an}的公差d≠0,且a1,a3,a9成等比数列,则(a3+a6+a9)/(a4+a7+a10)=____
设等差数列{An}的公差为2,且a1+a4+a7=10,则a3+a6+a9的值为?
已知等差数列{an}中,公差d>0,其前n项和为Sn,且满足a2·a3=45,a1+a4=14
等差数列an的公差为d ∈(0,1),且sin^2 a3 -sin^2 a7/sin(a3 a7)=-1 当n=10时,
{an}为等差数列,且a7-2a4=-1,a3=0,则公差d=? 求详细解释!我想要借助这个题来弄懂这一类题型,所以请各
已知数列{an}(n∈N*)是首项为1的等差数列,其公差d>0,且a3、a7+2、3a9成等比数列.
已知公差不为0的等差数列{an},a1=1,且a2,a4-2,a6成等差数列