How to solve for this question?

For the given function, nd the following 18x2 x+ 9 x} = (a) Use a geometric series to represent each function as a power series centered at 0. as H o (b) Determine the radius of convergence R and the interval of convergence. (Use symbolic notation and fractions where needed. For the second part of the question, give your answer as an interval in the form (*,*). Use the symbol 00 for innity, U for combining intervals, and an appropriate type of parenthesis "(" ")", "[" or " " depending on whether the interval is open or closed.)