TỔNG S = C20182 C20184 C20186 ...C20182016C20182018 BẰNGA. 22016....

Câu 21: Tổng S =

C

2018

2

C

2018

4

C

2018

6

...

C

2018

2016

C

2018

2018

bằngA.

2

2016

. B.

2

2017

1

. C.

2

2018

. D.

2

1009

1

.