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
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.
已知等差数列首项是a1,公差是d,bn=3an+4b,则数列是否为等差数列
已知等差数列An,且Ak与公差d均不为0,求证;方程Akx6
{an}为等差数列,an不等于0,d为公差,求证:1/(a1a2)+1/(a2a3)+...+1/(an-1*an)=(
已知公差为d的递增等差数列an ,满足a2a4=3,a1+a5=4,求公差d!
等差数列{an}中,公差d
等差数列an的公差d
等差数列{an}的公差d
已知等差数列{An}的公差d
已知等差数列an中,公差d
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.
已知数列{an}的通项公式为an=8-3n.[1]说明数列{an}是等差数列,并求出a1和公差d;