I need help with the zipper theorem proof.
what's the zipper theorem?
If series {a} and {b} go to L, then the series {c} consisting of osolating a, b members also goes to L. I don't know how to do subscripts on here, or I'd be more specific. It's second semester Calculus.
do you mean "sequence" or "series" ?
cause I don't think that's true for series, only sequences
begin by assuming the definition of convergence for each series \(\{a_n\},\{b_n\}\) and state those definition formally. \[\{a_n\}\to L\iff\exists N|\forall n>N,~~|a_n-L|<\epsilon\]
so you understand that definition and notation?
Omg, yes! Sequences! Series was last chapter. My bad.
do*
Yes. How do I go from there?
write the same definition for the sequence \(\{b_n\}\) using some other index, \(M\) in a sequence that consists of the elements a1, b1, a2, b2, ... you can then show that if you rename the indices of this sequence and write \(\{c_n\}=c_1,c_2,c_3,...\) you can figure out the index at which the same definition holds (hint: it can be written in terms of M and N; think of how the Nth term and Mth term relate to the new sequence))
if you need further help let me know
Thank you very much!
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