Find Limit of Xn as n Approaches Infinity

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The discussion revolves around finding the limit of the sequence defined by xn = 1/2(xn−1 + (3/xn−1)) as n approaches infinity, with the initial condition x1 = a (where a is not zero). Participants are asked to demonstrate their approach to solving the problem and identify where they encounter difficulties. Key points include the need to analyze the recursive formula and apply mathematical techniques to derive the limit. The conversation emphasizes the importance of showing work and reasoning in reaching a solution. Ultimately, the limit of the sequence as n approaches infinity is the focal point of the inquiry.
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Consider the sequence xn in which xn = 1/2(xn−1 + (3/xn-1) and x1 = a
(a not equals 0). Find lim n →∞ xn
 
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You need to show how you started the problem, and where you got stuck.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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