Sequences in complex (just a clarifying question)

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Homework Statement


(excuse lack of latex)
show that if SUM(zn)= S and SUM(wn= T, then SUM(zn + wn) = S + T

Homework Equations


The Attempt at a Solution



so if I'm doing this right, this is pretty easy, i think. they want me to use a theorem that says if zn=xn +iyn, and SUM(zn)= S, where S = X + iY, this happens iff SUM(xn)= X and SUM(yn)= Y.

so my question is am i allowed to say SUM(zn + wn) = SUM(zn) + SUM(wn) = SUM(xn) + iSUM(yn) + SUM(un) + iSUM(vn)? I'm not sure if I'm violating anything by breaking it up like this. it all follows very quickly from here.

*edit: forgot to erase double standard questions after preview
 
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You can break it up as:
SUM(xn+un)+iSUM(yn+vn)

just using the property that you posted (make sure you understand why). To go further you need to do something else
 
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