2 + 2^2 + 2^3 + ... + 2^9 = ?
Choose the correct option
A) 1000  B) 1011  C) 1019  D) 1021  E) 1022
This is a G.P. in which a = 2, r = 22 = 2 and n = 9.   2   Sn = a(rn - 1) / (r - 1)= 2 x (29 - 1) / (2 - 1)= 2 x (512 - 1) = 2 x 511 = 1022.   1022)
<result>E</result>
2 + 2^2 + 2^3 + ... + 2^9 = ?