I need help proving that if (xn) is a convergent series, then (xn)^2 is a convergent series.(adsbygoogle = window.adsbygoogle || []).push({});

also is (n^3)*(xn) is convergent, then (xn) is convergent. i reasoned that if (n^3)*(xn) is convergent, we know that (n^3)*(xn) > (xn) > 0, therefore by comparison test, (xn) is convergent.

determine whether or not the function exists and if it doesnt explain why:

lim x--> 0 (x^2/(|x|))

i cant put it in formal terms why this limit does not exist (we did not go over continiuty yet)

show that the function

f(x) = { x if x is rational, 0 if x is irrational

has a limit at p=0 and does not have a limit at any other point.

cant quite establish that the limit exists and how do i prove that no other points have limits?????

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# Homework Help: Series and limit help for analysis

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