已知等差數(shù)列{an}的前n項(xiàng)和為Sn,若OB=a100OA+a101OC,且A、B、C三點(diǎn)共線(該直線不過點(diǎn)O),則S200等于( ?。?A.100 B.101 C.200 D.201
已知等差數(shù)列{a
n}的前n項(xiàng)和為S
n,若
=a
100+a
101,且A、B、C三點(diǎn)共線(該直線不過點(diǎn)O),則S
200等于( ?。?br/>A. 100
B. 101
C. 200
D. 201
優(yōu)質(zhì)解答
∵向量
=a
100+a
101,
A、B、C三點(diǎn)共線,
∴a
100+a
101=1,
∴S
200=
(a
1+a
200)=100,
故選:A.
我來回答
類似推薦
- 已知等差數(shù)列{an}的前n項(xiàng)和為Sn,若向量OB=a1*向量OA+a200*向量OC,且ABC三點(diǎn)共線(該直線不過點(diǎn)O),則S200等于幾
- 已知等差數(shù)列﹛an﹜的前n項(xiàng)和為Sn,若向量OB=a2×向量OA+a2009×向量OC,且ABC三點(diǎn)共線
- 已知等差數(shù)列{an}的前n項(xiàng)和為Sn,若OB=a100OA+a101OC,且A、B、C三點(diǎn)共線(該直線不過點(diǎn)O),則S200等于( ) A.100 B.101 C.200 D.201
- 已知等差數(shù)列{an}的前n項(xiàng)和為Sn,若OB=a100OA+a101OC,且A、B、C三點(diǎn)共線(該直線不過點(diǎn)O),則S200等于( ?。?A.100 B.101 C.200 D.201
- 已知等差數(shù)列an,向量OB等于a1*向量OA+a200*向量OC,A,B,C三點(diǎn)共線,此線不過原點(diǎn),求S200
- You will ask for what you A will do B have done C had done D do 選B 為什么
- 計(jì)算:x-1的絕對(duì)值
- The two pictures look the same to me.It's hard to ( )one from the other.
- Recently,great changes have taken place in my home town.這句話成立嗎?
- 已知關(guān)于X的方程A(5X-3)=6X+10無解,試求A
- 三角形ABC中D在邊AB上角ACD等于角ABC,AC等于3,AD等于1則DB等于幾
- 我國最大的鹽場(chǎng)是_;我國最大的漁場(chǎng)是_.