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1.1. X Y X x Y (x, y) , x X, y Y.
1.2. X Y ( X Y) X x Y. X Y , X Y X.
1.1. X = { a, b, c, d }, Y = { 1, 2, 3, 4, 5 }. a={(a, 1), (b, 2), (c, 3), (d, 4)} X Y.
, a X x Y, (x, y),
a. , a= {(4, 4), (3, 3), (2, 2), (4, 2)} X = { 4, 3, 2 } "" .
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(x, y) a, : x a y. : x > y, a = b, 8 4, m || l, a b . .
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y = x2 +5x - 6
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x + y = ,
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: . X = { a, b, c, d, e }.
, . (OX - , OY - ) , X (. 1).
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. 1.
a, b, c, d, e , (x, y) , (x, y). 2 , a= {(a, b), (a, c), (b, d), (c, e), (e, b), (e, e)}.
. 2. a
. X ( ), (x, y) a (), x y. a 3.
. 3.
, , . X a. - X = { x1, x2,..., xn } A = [ aij ] :
, a, 3,
, , .