I am hopelessly confused on a homework assignment.

The problem says " (a) Find the series radius and interval of convergence. For what values of x does the series converge (b) absolutely, (c) conditionally?"

Attached is a sample of problems from the book.

Any help would be appreciated!

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These are power series. The radius of convergence is

$$\lim_{x\to\infty}\left|\frac{a_n_+_1}{a_n}\right|$$ then the series converges for

$$\lim_{x\to\infty}\left|\frac{a_n_+_1}{a_n}\right|<1$$

After that you find that the series converges say for x in the interval (a,b) and after that try to test whether the series converges at a and b, by letting x=a, and x=b respectively.

HallsofIvy