Find Limit of Sequence An: 1-1/(n(n+1)/2)

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Homework Statement



Find limit of sequence An=(1-1/3)(1-1/6)...(1-1/(n(n+1)/2))



Homework Equations





The Attempt at a Solution



I just found limit of 1-1/(n(n+1)/2) when n→∞,which is 1.Is that a proper solution?
 
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4c0 said:

Homework Statement



Find limit of sequence An=(1-1/3)(1-1/6)...(1-1/(n(n+1)/2))

Homework Equations


The Attempt at a Solution



I just found limit of 1-1/(n(n+1)/2) when n→∞,which is 1.Is that a proper solution?

Homework Statement


Homework Equations


The Attempt at a Solution


I believe they're asking you to find the limit of that infinite product, not just the final term (the limit of which is clearly 1, as you've found).

Try to find an expression for the general term in terms of n. It'll be a quotient. Factorise the numerator.

Now see what happens when you multiply one term by the next. Then multiply by the next. Do this until you see a pattern emerging. What terms cancel out and what are you left with?
 
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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