Testing the Convergence of Series: A Counterexample

DEMJ
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Homework Statement



If \sum_{k=1}^{\infty} a_k converges and a_k/b_k \to 0 as k\to \infty, then \sum_{k=1}^{\infty} b_k converges.

Homework Equations


It is true or false.

The Attempt at a Solution


I think it is false and here is my counterexample. Let a_k = 0,b_k=\frac{1}{k}. This satisfies our initial conditions of \sum_{k=1}^{\infty} a_k converges and a_k/b_k \to 0 as k\to \infty but \sum_{k=1}^{\infty} b_k diverges.
Is this correct?
 
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Looks okay.

Your counterexample also looks correct, if you want to make it slightly less trivial you could use
a_k = \frac{1}{k^2}
instead :)
 
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