A small error in your algebra ... but you still got the right answer!
. . The interval of convergence is: .
. . And the radius of convergence is: .
I've posted a few steps of the problem i solved in the pic: http://img180.imageshack.us/img180/9913/26377643by1.png
however, what is the radius of convergence? i got the interval to be [0, 1]
do i just solve for x for the radius? |(2x-1)|