Question

2+2square+-----+2power of eight=??

Answer 1

take the short form of the series.

=> 2 + 2 + 2^2 + 2^3

=> 2(1 + 1 + 2 + 2^2)

=> 2(2 + 2 + 2^2)

=> 2x2 (1 + 1 + 2)

=> 2x2x2 ( 1+1)

=> 2^3 (2) = 2^4  

Through same mechanism given sequence will end in 2^8  = 2^9