- #1
Calu
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- 0
Homework Statement
I have been asked to prove the convergence or otherwise of ∑∞n=1 n/(3n + n2).
In the example solution, with the aim to prove divergence by comparison with the Harmonic Series, the lecturer has stated that n/(3n + n2) ≥ n/(4n2) = 1/4n and which diverges to +∞.
I was wondering how to arrive at the decision to write n/(3n + n2) ≥ n/(4n2) came from, and how I would arrive at a similar inequality in further examples.