Find the general formula for this Macluaurin series 
I've tried looking at video examples from my e-book, khanacademy, I can't find anything to explain this. My homeworks tutorial problems are always really confusing, they use terms when the book uses SOMETHING else. To make things worse you get 5 attempts so I'm discouraged from trying the problem again myself in case I mess up :[
Isn't a general formula the generic formula for any maclaurin series? I don't get what they even want me to do...

you have
$f(x) = 8 + 16 x + 24 x^2 + 32 x^3 + 40 x^4\cdots$ factor out an 8.
$f(x) = 8(1 + 2 x + 3 x^2 + 4 x^3 + 5 x^4\cdots)$
look for a pattern
$f(x) = 8(1 + 2 x + 3 x^2 + 4 x^3 + 5 x^4\cdots (n+1) x^n\cdots)\\
\sum_\limits{n=0}^\infty 8(n+1)x^n$
