Recent content by DEMJ

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    Abstract Algebra: Groups of Permutations

    Also, I still do not understand how to list all the elements because this is the only element I know how to find. Should I do (234165)^3, (234165)^4, ... on up to what exponent?
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    Abstract Algebra: Groups of Permutations

    Ok so I could write an element as (234165)^2 as \left(\begin{array}{llllll} 1 & 2 & 3 & 4 & 5 & 6\\ 2 & 3 & 4 & 1 & 6 & 5\\ \end{array}\right) \circ \left(\begin{array}{llllll} 1 & 2 & 3 & 4 & 5 & 6\\ 2 & 3 & 4 & 1 & 6 & 5\\ \end{array}\right) = (3412)(56)
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    Abstract Algebra: Groups of Permutations

    So that is one element, right? But how do I go about finding the rest. And more important, how could I know exactly how many elements there will be?
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    Abstract Algebra: Groups of Permutations

    I don't understand because on the wiki page above it says that (1 2 3 4 5 6)^2 = (1 3 5)(2 4 6) but when I compose (123456) with (123456) = (123456). I guess I am just royally confused.
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    Abstract Algebra: Groups of Permutations

    What do you mean take the powers of the element? Could you give me an example of one? Thank you so much.
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    Abstract Algebra: Groups of Permutations

    Homework Statement List the elements of the cyclic subgroup of S_6 generated by f = \left(\begin{array}{llllll} 1 & 2 & 3 & 4 & 5 & 6\\ 2 & 3 & 4 & 1 & 6 & 5\\ \end{array}\right)Homework Equations The Attempt at a Solution I really do not understand what the elements of a permutation really...
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    Does the Series Converge with Conditionally Convergent Multipliers?

    You are right, I owned my self by basic algebra :-p
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    Does the Series Converge with Conditionally Convergent Multipliers?

    that would make a_k b_k = \frac{(-1)^{2k}}{k} which is convergent, I think. I meant what I put but apparently it does not work?
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    Does the Series Converge with Conditionally Convergent Multipliers?

    Homework Statement If a_k is decreasing and it's limit is 0 as k \to \infty and \sum_{k+1}^{\infty} b_k converges conditionally, then \sum_{k=1}^{\infty} a_k b_k converges Homework Equations This is true or false. The Attempt at a Solution I think it is false because if we let...
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    Testing the Convergence of Series: A Counterexample

    Homework Statement If \sum_{k=1}^{\infty} a_k converges and a_k/b_k \to 0 as k\to \infty, then \sum_{k=1}^{\infty} b_k converges.Homework Equations It is true or false.The Attempt at a Solution I think it is false and here is my counterexample. Let a_k = 0,b_k=\frac{1}{k}. This satisfies our...
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    LaTeX Fix Latex Trouble w/ Duplicate Text - Physics Forums

    I just made a thread here https://www.physicsforums.com/showthread.php?t=399124 and now whenever I try to use latex to create a new thread I get the same latex stuff from this thread I linked. Here for example lol a^2 \sup hi how are you and what I typed for each one is [.tex]lol[/tex]...
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    Absolute Convergence Proof: The Relationship Between a_k and b_k

    Homework Statement if a_k \le b_k for all k \in \mathbb{N} and \sum_{k=1}^{\infty} b_k is absolutely convergent, then \sum_{k=1}^{\infty} a_k converges. Homework Equations It's either true or false. The Attempt at a Solution I think a counterexample to prove it's false is if we...
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    Writing 2^{1-i} using Euler's Formula

    Homework Statement Use Euler's formula to write 2^{1-i} in the form a+ib. The Attempt at a Solution I know this has to be so simple because I could do this easy if the question was to write e^{1-i} in the form a+ib using Euler's. So what I do not understand is how does 1-i being...
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    How to Multiply Permutations: A Quick Guide for Beginners

    I am doing awful with this, but I understand (47) sends 7 to 4, but I do not understand where (12) sends 7 -> 4 to? If it sends it (246) does it change (246) to (276) ?
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    How to Multiply Permutations: A Quick Guide for Beginners

    If I start at the right 7 -> 4 then 4 goes back to 7. Then 2 -> 1 then 1 goes back to 2. or should I think of it as 7 -> 4 then 4 -> 2 then 2 -> 1 then 1 -> 6 and so on. Which is the correct way to think for permutation multiplication?
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