a1=1,an=(1/2)x(4/3)^(n-2)n>=2則a2n=(1/2)x(4/3)^(2n-2) n=1,2,3,4,5.
則和為;(1/2)^nx[3x(4/3)^n-3]
設(shè)數(shù)列{an}前n項(xiàng)和為Sn,且a1=1,a(n+1)=1/3sn,n=1,2,3……,求a2+a4+a6+……+a2n的值
設(shè)數(shù)列{an}前n項(xiàng)和為Sn,且a1=1,a(n+1)=1/3sn,n=1,2,3……,求a2+a4+a6+……+a2n的值
數(shù)學(xué)人氣:699 ℃時(shí)間:2020-02-03 04:38:06
優(yōu)質(zhì)解答
我來(lái)回答
類似推薦
- 數(shù)列{an}的前n項(xiàng)和為Sn,且a1=1,a(n+1)=1/3Sn,n=1,2,3,.(1)求通項(xiàng)公式 (2)a2+a4+a6+.+a2n的
- 數(shù)列(An)的前n項(xiàng)和為Sn,且A1=1,An+1=1/3Sn,n=1,2,3.,求A2,A3,A4的值及數(shù)列(An)的通項(xiàng)公式
- 數(shù)列{an}的前n項(xiàng)和Sn,且a1=1,an+1=1/3Sn,n=1,2,3……求(1)a2,a3,a4的值及{an}的通項(xiàng)公式;(2)a2+a4+a6+……+a2n的值.
- 數(shù)列{an}的前n項(xiàng)和為sn且a1=1 an+1=1/3sn求a2,a3,a4及an
- 設(shè)數(shù)列{An}的前n項(xiàng)和為Sn若An+1=3Sn,a1=1則a6=
- 一元一次方程x2+(2m-1)x+m2=0,有兩個(gè)實(shí)數(shù)根x1,x2 (1)求實(shí)數(shù)m的取值范圍 (2)當(dāng)x12-x22=0時(shí),求m
- 城市污染對(duì)人類有何危害
- ______ a lot of books,the boy knows much more than the boys of his age.
- Lucy often does her homework at school改為一般疑問(wèn)句
- 我父親似乎很高興.My father ___ ___ ____ happy.
- much to 和 many 區(qū)別
- You are my little little apple~誰(shuí)會(huì)翻譯吶
猜你喜歡
- 1描寫霧海 的四字詞語(yǔ)
- 2填空1:he always gets to school by s( ).2:it is ten minutes h( ) from my home to school
- 3我國(guó)唯一注入北冰洋的河流是哪條河流
- 4就是做題時(shí)候在化學(xué)式下方量的書寫方法.1:1的含義、
- 5將50mL4mol/L的AlCl3溶液與4mol/L的NaOH溶液反應(yīng)后得沉淀7.8g,所消耗NaOH溶液的體積為多少mL?
- 6幾個(gè)數(shù)的最大公因數(shù)是最小公倍數(shù)的()數(shù),幾個(gè)數(shù)的最小公倍數(shù)是最大公因數(shù)的()數(shù)
- 7需要英語(yǔ)的春節(jié)短語(yǔ)!
- 8酸根離子指什么?
- 9求解軌跡問(wèn)題
- 10設(shè)f(x)=ax^2+bx+c(a≠0) ; 若f(x+1)=f(-x),求證-b/2a=1
- 11英語(yǔ)翻譯
- 12怎么做啊?要過(guò)程.某電視機(jī)廠某型號(hào)電視比去年增產(chǎn)40%,實(shí)際比計(jì)劃多生產(chǎn)20%,此型號(hào)電視今年實(shí)際產(chǎn)量是去年的( )%?