数列求证题设等差数列{An}的公差为d,d>0,数列{B}是公比为q等比数列,且B1=A1>0.若A2=B2,求证：当n>2时,An

数列求证题设等差数列{An}的公差为d,d>0,数列{B}是公比为q等比数列,且B1=A1>0.若A2=B2,求证：当n>2时,An 设数列｛an｝是各项为正等比数列 求证数列｛lgan｝为等差数列,并写出首项和公差 设等差数列an的公差为d,若数列{2^(a1an)}为递减数列,则：A d>0 B d0 D a1d 已知数列{lgan}是首项为3,公差为2的等差数列,求证:{an}是等比数列. 等差数列{an}的公差为d,则数列a1+a4,a2+a5,a3+a6,.是什么数列 在数列{an}和{bn}是两个无穷等差数列,公差分别为d1和d2,求证：数列{an+bn}是等差数列,并求它的公差. 已知等差数列{an}的公差为d,求证：am-an/m-n=d 已知等差数列｛An｝的公差为d,求证:(Am-An)/(m-n)＝d 已知等差数列{an}的公差为d.求证m-n分之am-an=d. 设数列{an}的前n项和为Sn,若{an}和{根号sn+n}都是公差为d的等差数列,则a1= 设数列｛an｝是首项为3,公差为d的等差数列,又数列｛bn｝是由bn=an+an+1所决定的数列,那么数列｛bn｝前n项和sn是多少? 求证等差数列已知{an}为等差数列,公差d=3,求证：{2*an+3}是等差数列并求公差d 在以d为公差的等差数列an中,设S1=a1+a2.+an,S2=an+1+an+2+a2n,S3=a2n+1+a2n+a3n,求证S1,S2,S3,也是等差数列,并求其公差 若数列{an}是公差为d的等差数列,则数列{an+2a(n+2)}是公差为多少的等差数列 数列{an}是公差为d的等差数列,用定义法证明数列{a（4n-3）}是等差数列 设an是等比数列,且an＞0,求证数列｛lgan}为等差数列,并写出首项与公差.答的好设an是等比数列,且an＞0,求证数列｛lgan}为等差数列,并写出首项与公差.答的好就采纳. 设等差数列an的公差为d不等于0,前n项和为Sn.则Sn为递增数列的充分必要条件是 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