Câu 11:
Tính tổng S=1+2.2+3.22+4.23+........+2018.22017S = 1 + 2.2 + {3.2^2} + {4.2^3} + ........ + {2018.2^{2017}}S=1+2.2+3.22+4.23+........+2018.22017
