设数列{an}的前n项和是Sn,Sn满足:S1=a(a≠0),Sn+1 =3Sn+1(n∈N*),数列{bn}满足:bn+2 =2bn+1-bn,且
题目
设数列{an}的前n项和是Sn,Sn满足:S1=a(a≠0),Sn+1 =3Sn+1(n∈N*),数列{bn}满足:bn+2 =2bn+1-bn,且
设数列{an}的前n项和是Sn,Sn满足:S1=a(a≠0),Sn+1 =3 Sn+1(n∈N*),数列{bn}满足:bn+2 =2bn+1-bn (n∈N*),且b3=3,b5=9.
(1)分别求数列{an}和{bn}的通项公式;
(2)若a=1,若对任意的n∈N*,都有(Sn+1/2)*k≥bn恒成立,求实数k的取值范围.
答案
举一反三
已知函数f(x)=x,g(x)=alnx,a∈R.若曲线y=f(x)与曲线y=g(x)相交,且在交点处有相同的切线,求a的值和该切线方程.
我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
最新试题
热门考点