basically on the interval 1 to infinity the constant '9' really has no bearing because it becomes a non-factor. So the problem reduces to (k/k^2)

k/k^2 reduces to 1/k

as the limit approaches infinity you get 1/2,1/3,1/4,1/5.....1/x so you see the number is getting smaller and smaller, thus the limit approaches 0. Since the series approaches a finite number the series converges. If it went to infinity it would diverge.

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