Proving Convergence of \{b_n\} when \{a_n\}\to A, \{a_nb_n\} Converge

Dustinsfl
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If \{a_n\}\to A, \ \{a_nb_n\} converge, and A\neq 0, then prove \{b_n\} converges.

Let \epsilon>0. Then \exists N_1,N_2\in\mathbb{N}, \ n\geq N_1,N_2

|a_n-A|<\frac{\epsilon}{2}

And let \{a_nb_n\}\to AB

So, |a_nb_n-AB|<\epsilon

I don't know how to show b_n is < epsilon.
 
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Hi Dustinsfl! :smile:

Hint: an(bn - B) :wink:
 
tiny-tim said:
Hi Dustinsfl! :smile:

Hint: an(bn - B) :wink:

I am don't understand, so we have:

(a_nb_n-a_nB)

Ok, now what?
 
limn->∞ :wink:
 
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