How Do You Find the Limit of the Series S_n = \dfrac {3}{8}⋅\dfrac {4^n}{3^n}?

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chwala
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Homework Statement
See attached.
Relevant Equations
Limits
Consider the series below;

1644709958718.png


From my own calculations, i noted that this series can also be written as ##S_n##=##\dfrac {3}{8}##⋅##\dfrac {4^n}{3^n}##. If indeed that is the case then how do we find the limit of my series to realize the required solution of ##1## as indicated on the textbook? I tried taking limits...L Hopital's rule... and still got ##∞## implying divergence. Are we required to solely maintain the series in the pattern indicated on the text and not any other way?

In other words, if one was given a specific question to find the limit of my series ##S_n##=##\dfrac {3}{8}##⋅##\dfrac {4^n}{3^n}##in an exam, then would it be correct to state ##∞##?
 
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Your formula is wrong. You probably fit it to the first two values, and didn't check if it matches anything else.
 
Office_Shredder said:
Your formula is wrong. You probably fit it to the first two values, and didn't check if it matches anything else.
True it is wrong...i ought to have checked if it applies to the sequence ##S_3##...but we could also have
...our series ##\dfrac {1}{2}##, ##\dfrac {2}{3}##, ##\dfrac {3}{4}##,##\dfrac {4}{5},##... as
##S_n##=##\dfrac {n}{1+n}##
Cheers :cool:
 
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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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