Recent content by Gavran

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    Finding the number of ways to arrange identical balls in a circle

    For more complicated problems than this one in the original post the formula is $$ N=\frac1n\sum_{d|gcd(n_1,n_2,...,n_k)}^{}\phi(d)\binom{n/d}{n_1/d,n_2/d,...,n_k/d} $$ where: ## n ## - the number of balls, ## k ## - the number of colors, ## n_i ## - the number of balls of the i-th color, ##...
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    Finding the number of ways to arrange identical balls in a circle

    You do not need any formula to solve this problem. With two blue balls and two red balls you have two cases BBRR and BRBR. How many different options do you have when you insert the yellow ball into BBRR? How many different options do you have when you insert the yellow ball into BRBR?
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    B Onto set mapping is the surjective set mapping, and into injective?

    The first statement of the theorem was published in 1887 by Georg Cantor. If M and N are two such sets that components M' and N' can be separated from them, of which it can be shown that |M|=|N'| and |M'|=|N|, then M and N are equivalent sets.
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    I About the existence of Hamel basis for vector spaces

    The answer to the post #8: Yes, it does.
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    I About the existence of Hamel basis for vector spaces

    The Axiom of Choice and the existence of a Hamel basis imply each other.
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    I About the existence of Hamel basis for vector spaces

    A ⇔ B The exclusion of A does not produce B is false.
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    I About the existence of Hamel basis for vector spaces

    It can be shown that if the Axiom of Choice is false, then there are vector spaces with no Hamel basis. The exclusion of the Axiom of Choice means the exclusion of the proof based on the Axiom of Choice and this does not mean there are vector spaces with no Hamel basis. Every vector space has a...
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    B Onto set mapping is the surjective set mapping, and into injective?

    You already have the proof of the theorem on page 29 of the book. By the way, the more common statement of the Schroeder-Bernstein theorem is this: if there are injections f : A → B and g : B → A, then there is a bijection h : A → B.
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    I Determine whether ##125## is a unit in ##\mathbb{Z_471}##

    Although you have not used the standard step-by-step approach, your solution is also correct.
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    I Determine whether ##125## is a unit in ##\mathbb{Z_471}##

    The back-substitution in the context of the Euclidean algorithm is: 1=9-4⋅2, 2=29-3⋅9, 1=9-4⋅(29-3⋅9)=-4⋅29+13⋅9, 9=96-3⋅29, 1=-4⋅29+13⋅(96-3⋅29)=13⋅96-43⋅29, 29=125-1⋅96, 1=13⋅96-43⋅(125-1⋅96)=-43⋅125+56⋅96, 96=471-3⋅125, 1=-43⋅125+56⋅(471-3⋅125)=56⋅471-211⋅125=260⋅125.
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    B Onto set mapping is the surjective set mapping, and into injective?

    To be on the set means occupying the whole set in a particular way and the word “onto” follows the definition of a surjective function at all. To be in the set means occupying the part of the set but it does not mean that every element of the part of the set is occupied only once and this is the...
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    I Useless continued fraction for 1

    This is not a simple continued infinite fraction. $$ a_0+\frac{1}{a_1+\frac{1}{a_2+\frac{1}{a_3+\frac{1}{...}}}} $$ All integers in the sequence ## \{a_i\} ##, other than the first, must be positive.
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    I Useless continued fraction for 1

    It can be proved that the sequence of convergents of any simple continued infinite fraction converges.
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    I Direction Fields and Isoclines

    ODE | Slope fields and isoclines example
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    I Detail of Diagonalization Lemma

    The question is more general than it looks and there is a difference between the coded term and the name of the coded term. For example, The coded term is 1. The name of the coded term is 1. In the first case 1 presents the coded term while in the second case 1 presents the symbol which is used...
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