首页
在正项数列{an}中,令Sn=.(Ⅰ)若{an}是首项为25,公差为2的等差数列,求S10...
试题详情
在正项数列{a
n}中,令S
n=
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAGIAAAAsCAYAAACe920SAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
.
(Ⅰ)若{a
n}是首项为25,公差为2的等差数列,求S
100;
(Ⅱ)若
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAGAAAAAsCAYAAACaAr0vAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
(P为正常数)对正整数n恒成立,求证{a
n}为等差数列;
(Ⅲ)给定正整数k,正实数M,对于满足a
12+a
k+12≤M的所有等差数列{a
n},求T=a
k+1+a
k+2+…a
2k+1的最大值.
相关试题
-
在正项数列{an}中,令Sn=
.
(Ⅰ)若{an}是首项为25,公差为2的等差数列,求S100;
(Ⅱ)若
(P为正常数)对正整数n恒成立,求证{an}为等差数列;
(Ⅲ)给定正整数k,正实数M,对于满足a12+ak+12≤M的所有等差数列{an},求T=ak+1+ak+2+…a2k+1的最大值.
-
在正项数列{an}中,令Sn=
.
(Ⅰ)若{an}是首项为25,公差为2的等差数列,求S100;
(Ⅱ)若
(P为正常数)对正整数n恒成立,求证{an}为等差数列;
(Ⅲ)给定正整数k,正实数M,对于满足a12+ak+12≤M的所有等差数列{an},求T=ak+1+ak+2+…a2k+1的最大值.
-
在正项数列{an}中,令Sn=
.
(Ⅰ)若{an}是首项为25,公差为2的等差数列,求S100;
(Ⅱ)若
(P为正常数)对正整数n恒成立,求证{an}为等差数列;
(Ⅲ)给定正整数k,正实数M,对于满足a12+ak+12≤M的所有等差数列{an},求T=ak+1+ak+2+…a2k+1的最大值.
-
已知一个数列{an}的各项是1或2.首项为1,且在第k个1和第k+1个1之间有f(k)个2,记数列的前n项的和为Sn.
(1)若f(k)=2k-1,求S100;
(2)若f(k)=2k-1,求S2011.
-
已知{an}是首项为19,公差为-4的等差数列,Sn为{an}的前n项和.
(Ⅰ)求通项an及Sn;
(Ⅱ)设{bn-an}是首项为1,公比为2的等比数列,求数列{bn}的通项公式及其前n项和Tn.
-
已知{an}是首项为19,公差为-2的等差数列,sn为{an}的前n项和.
(1)求通项an及sn;
(2)设{bn-an}是首项为1,公比为3的等比数列,求数列{bn}的通项公式及其前n项和Tn.
-
已知{an}是首项为19,公差为-4的等差数列,Sn为{an}的前n项和.
(Ⅰ)求通项an及Sn;
(Ⅱ)设{bn-an}是首项为1,公比为2的等比数列,求数列{bn}的通项公式及其前n项和Tn.
-
已知{an}是首项为19,公差为-2的等差数列,sn为{an}的前n项和.
(1)求通项an及sn;
(2)设{bn-an}是首项为1,公比为3的等比数列,求数列{bn}的通项公式及其前n项和Tn.
-
已知{an}是首项为19,公差为-4的等差数列,Sn为{an}的前n项和.
(Ⅰ)求通项an及Sn;
(Ⅱ)设{bn-an}是首项为1,公比为2的等比数列,求数列{bn}的通项公式及其前n项和Tn.
-
已知{an}是首项为19,公差为-4的等差数列,Sn为{an}的前n项和.
(Ⅰ)求通项an及Sn;
(Ⅱ)设{bn-an}是首项为1,公比为2的等比数列,求数列{bn}的通项公式及其前n项和Tn.