So, why not differentiating this result and see what you get?
As for 4), you're expected to know that then what would be a series representation for ?
I have to find a power series representation for the following:
1)
2)
3)
4)
Well, I know that the sum of
Therefore the sum of x^(3n)
But I don't know how to relate the others to each other they look similar, so any hins would be greatly appreciated. Thanks!