I stuck with this problem.
Find the interval of convergence of
(x^2n)/((-3)^n)
I already found out that the boundaries of this Interval are −3 and 3.
When I try to check the boundaries Insertertet, I get the soultion, that both have to be excluded. But one Series calculator in the Internet said, −3 has to be included. That confuses me, because when I insert this boundary, i get the same series as when I insert the other boundaries.
I am very thankful for any advises!
Find the interval of convergence of
(x^2n)/((-3)^n)
I already found out that the boundaries of this Interval are −3 and 3.
When I try to check the boundaries Insertertet, I get the soultion, that both have to be excluded. But one Series calculator in the Internet said, −3 has to be included. That confuses me, because when I insert this boundary, i get the same series as when I insert the other boundaries.
I am very thankful for any advises!