Series Sum help (1 Viewer)

[FancyPenguin]

find the sum of the first 10 terms of the series

3+7+13+...+ [2^n+(2n-1)]

I have no idea how to find the ratio from this, all I've done is just find the individually and add them together but I'd really like to know how to find r and do this question using a formula

 

[FrankXie]

it is good to separate the whole sum into two parts. one of them is a GP, for which there is an "r", but the other is an AP, for which there is a "d", not an "r"