I need some help on the following

Determine the interval of convergence of the power series

infinity

sum of series (-1)^n/(n+3)4^n * (x-1)^n

n=1

I have

Here An = (-1)^n/(n+3)4^n, for n=1,2....

1. since

|An+1/An| = 1/(n+4)4^n+1 * (n+3)4^n/1

= ? ----> as n ----> ?

we have R = ? , by the Ratio Test.

Thus

2. If x = ? , the the power series is

?

Hence the interval of convergence is ( ? )