Recent content by swtlilsoni

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    Cannot find the pattern in recurrence relation

    Homework Statement I am doing a power series solution for: (x^2-1)y" + 8xy' + 12y = 0 I rewrote it in terms of power series and transformed everything into one series and finally ended up with the following recurrence relation: an+2= ((n+3)(n+4)an)/((n+2)(n+1)) I plugged in values for n...
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    Power series solution to a differential equation

    Okay thank you. I did not know I had the freedom to choose any point. I thought the answer varied depending on the chosen point so I thought it needed to be specified.
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    Power series solution to a differential equation

    Right given an equation p(x)y" + q(x)y' + r(x)y=0, an ordinary point is any point at which p(x0) does not equal 0. Thus in this equation, the singular points are -1, and 1. Does that mean I can choose any number that works as an ordinary point and plug it in for x0? I can choose 9? And plug...
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    Power series solution to a differential equation

    Homework Statement Using a power series solution, what is the solution to: (x^2-1)y" + 8xy' + 12y = 0 Homework Equations Normally these questions specify (about x0=0) but this one doesn't specify about which point. So if I use the power series equation, what am I supposed to plug in...
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    Proving the Recursive Fibonacci Problem: Is (Fn+1+Fn-1)Fn always a Fibonacci?

    good morning! okay so it seems like these proofs are to prove a given number is fibonacci? so do you mean I should solve for the number in terms of n, then try to use one of those proofs to show it is fibonacci?
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    Which recurrence relation is greater?

    Here is what my professor wrote (I don't completely understand what he did): An= c1\alphan + c2\betan c1,c2= 3 \pm \sqrt{}15 Bn= c3\deltan + c4\varpin c3,c4= (5 \pm \sqrt{}61)/2 3+\sqrt{}15=\alpha=6.8 3-\sqrt{}15=.9n = approaching zero (5 + \sqrt{}61)/2 = \delta = 6.5 (5 - \sqrt{}61)/2...
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    Combinatorics Problem: Sending 15 Postcards to 15 Friends in Unique Ways

    it's because it has to be multiplied. For every rearrangement of five identicals, there are two more rearrangements of the others
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    Which recurrence relation is greater?

    Homework Statement An+2=6An+1+6An A1=A2=1 Bn+2=5Bn+1+9Bn B1=B2=10100 a) is it true that Bn>An for every integer n > 0? b) is it true that Bn>An for infinetly many integers n>0? The Attempt at a Solution It just seems like these are increasing functions since they both start with...
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    Find a recurrence relation from a sequence of integers

    If you are given a sequence of integers such as: An=xn+yn where x and y are integers. and n=0,1,2,3... how would one find the recurrence relation? I tried writing An+1 in terms of An but it doesn't come out neatly because it doesn't translate so well. And there are terms raised to the n+1...
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    Proving the Recursive Fibonacci Problem: Is (Fn+1+Fn-1)Fn always a Fibonacci?

    Yes, the fibonacci formula I know. It is this: http://mathworld.wolfram.com/BinetsFibonacciNumberFormula.html right? But I tried writing it in terms of the formula, but there was no way of showing whether the end result is a fibonacci or not.
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    How do you solve third order recurrence relations?

    I know how to solve second order ones, but how would you solve third order ones? Because the characteristic polynomial would have a third degree so how can one find the roots? I have looked everywhere online to find out but I can't find anything. Please Please tell me!
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    Solve Recurrence Relation: A0,A1,A2 Given

    Homework Statement An=3An-2-2An-3 When A0=3 A1=1 A2=8 I tried to solve it normally like a normal recurrence relation however since it is not A sub n-1, it turns into a polynomial where the variable is raised to the third power which I couldn't factor and the whole thing turned into a mess.
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    Combinatorics Problem: Sending 15 Postcards to 15 Friends in Unique Ways

    because there are three sets of five identicals
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    Proving the Recursive Fibonacci Problem: Is (Fn+1+Fn-1)Fn always a Fibonacci?

    Homework Statement Is: (Fn+1+Fn-1)Fn always a Fibonacci? The Attempt at a Solution I have no clue! I know I'm supposed to show work and all but I'm so lost, any direction would be appreciated. Even if you just give me a link to read.
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