Câu hỏi
Tổng \(S = \frac{1}{{2017}}(2.{\mkern 1mu} 3C_{2017}^2 + 3.{\mkern 1mu} {3^2}C_{2017}^3 + 4.{\mkern 1mu} {3^3}C_{2017}^4 + ...\)\( + k.{\mkern 1mu} {3^{k - 1}}C_{2017}^k + ... + 2017.{\mkern 1mu} {3^{2016}}C_{2017}^{2017})\) bằng
- A
\({{4}^{2016}}-1.\)
- B
\({{3}^{2016}}-1.\)
- C
\({{3}^{2016}}.\)
- D \({{4}^{2016}}.\)
Câu hỏi trước
