Proving Convergence: Bounded Sequences and Absolute Convergence Test

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1. Prove that if a sequence (bn) is bounded and the sum |(an)| going from n= 1 to infinity converges, then the sum of the product of sequences (an)(bn) converges.



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3. Given that the sequence bn is bounded it is convergent, and by the absolute convergence test if the sum of the absolute value of the sequence (an) converges then so does the sum of the sequence of (an), therefore the sum of the product of the sequences an and bn converges.
 
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A bounded sequence is not necessarily convergent.
 
Oh yes that's true. So can I say that the sum of the product of a bounded sequence times a convergent sequence will be convergent? I'm assuming that the bounded sequence bn times the convergent sequence an will make the sum of their product convergent
 
Bellarosa said:
Oh yes that's true. So can I say that the sum of the product of a bounded sequence times a convergent sequence will be convergent? I'm assuming that the bounded sequence bn times the convergent sequence an will make the sum of their product convergent

Sure you can 'say that'. Anybody can 'say that'. Aren't you supposed to 'prove that'? I would think about setting up a comparison test...
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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