TỔNG C12019 C20192  C20193  ...  C20192018 C20192019 BẰNG A. 2...

Câu 4: Tổng C

12019

C

20192

C

20193

 ...  C

20192018

C

20192019

bằng

A. 2

2019

 1 . B. 2

2019

. C. 2

2018

. D. 2

2018

 1 .