Does the Maximum of Two Convergent Series Also Converge?

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SUMMARY

The discussion centers on proving that the series Ʃ from n=1 to ∞ max(an, bn) converges, given that both Ʃ from n=1 to ∞ an and Ʃ from n=1 to ∞ bn are convergent series with non-negative terms. The key insight is the application of the inequality max(a, b) ≤ a + b, which ensures that the maximum of two convergent series also converges. This conclusion is supported by the Cauchy criterion for convergence, confirming that the series of maximum values inherits the convergence property from the original series.

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Homework Statement


Let Ʃ from n=1 to ∞ an and Ʃ from n=1 to ∞ bn be convergent series, with an\geq0 and bn\geq0 for all n\inN. Show that the series Ʃ from n=1 to∞ max(an,bn) converges.



Homework Equations


I'm guessing it's got something to do with the cauchy criterrion for convergence of series but I'm not sure where to begin? Any hints would much appreciated
 
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I would write

2 max(a,b)=a+b+|a-b|

or

max(a,b)<=a+b

Either of which obviously converge.
 

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