Do These Complex Sequences Converge?

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SUMMARY

The discussion focuses on determining the convergence of four complex sequences. Sequences 1 and 2, namely 1, i, -1, -i, and 1, i/2, -1/3, -i/4, do not converge due to their oscillating nature. In contrast, sequences 3 and 4, represented as (1+i)/2 and (3+4i)/5, are suggested to converge, with the limit of sequence 3 being 1/2 + 1/2i. The discussion emphasizes the need for convergence tests, such as the Cauchy criterion, to analyze these sequences further.

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Homework Statement



I need to find if sequences have limits
1. 1,i,-1,-i,1,i,-i,1...
2. 1,i/2,-1/3,-i/4,1/5...
3. (1+i)/2,...,[(1+i)/2]^n
4.3+4i/5,...[(3+4i)/5]^n

Homework Equations





The Attempt at a Solution


I say 1 and 2 don't have limits because of the sign changes.
I say 3 and 4 have limits, but am not sure on how to find them.
3.1/2+1/2i
4.?
 
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What tests do you have to determine if a sequence converges or not? e.g. see if it's Cauchy. Write down some, and see if they apply
 

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