Question

for input k, output the kth power sum formula?

Answer 1

\[\sum_{n=1}^{n=k} a r^n=\frac{a}{1-r}-ar^k=a\frac{1-r^k+r^{k+1}}{1-r}\]

Answer 2

what is r suppose to represent?

Answer 3

oh never mind

Answer 4

"a" would just be some constant

Answer 5

so i would just write a program for that sum?

Answer 6

im kinda lost, more explanation please :)

Answer 7

i guess that the problem means i need a program for the power sum, for example: