Calculus
posted by Steven on .
I'm trying to find the radius of convergence for
$(x2)^n/(2x+1)
I did the ratio test and ended up with:
absolute value[(x2)/(2x+1)]<1
How would I solve for the inequality at this point?

If (x2)/(2x+1) < 1 then
(x2)^2 < (2x+1)^2
x^2  4x + 4 < 4x^2 + 4x + 1
3x^2 + 8x  3 > 0
x < 3 or x > 1/3