Элементы теории множеств: Учебно-методическое пособие для вузов

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  • - 20 2007 , 4

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    1 , 010101 (010100) - 010100 (510100) -

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    14

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    16

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    17

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    f : X Y , g : X Y f = g, X = X , Y = Y f(x) = g(x) x X.

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    18

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    19

  • 1. , , . , - f : X Y , f(x) = y0, x X . x1, x2 X, x1 6= x2. A = {x1}, B = {x2}. AB = , , f(AB) = , f(A) f(B) = {y0}.

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    (4). x f1(A B), f(x) A B, . .f(x) A f(x) B, , x f1(A) x f1(B), x f1(A)f1(B). , x f1(A)f1(B), x f1(A) x f1(B), , f(x) A f(x) B, f(x) AB, x f1(A B).

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    20

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    (g f)(x) = g(f(x)),x X.

    6. f, g : R R,