Page 9 - Buku Siap OSN Matematika SMP 2015(1)

NOTATIONS

 the set of positive integers (natural numbers)

 0 the set of non-negative integers
 the set of integers

  the set of positive integers
 the set of rational numbers

  the set of positive rational numbers

 0  the set of non-negative rational numbers
 the set of real numbers

m, n the lowest common multiple of the integers m dan n

(m, n) the greatest common devisor of the integers m dan n
a  b a devides b
x absolute value of x

x  
  the greatest integer not greather than x
x  
  the least integer not less than x
 
{x} the decimal part of x, i.e. {x} = x – x  
a  b (mod c) a is congruent to b modulo c
 n
  the binomial coefficient n choose k
 
k
 
n! n factorial, equal to the product 1  2  3  n
 ,a b  the closed interval, i.e. all x such that a  x  b

(a,b) the open interval, i.e. all x such that a < x < b
 iff, if and only if
 implies

A  B A is a subset of B

A  B the set formed by all the elements in A but not in B
A  B the union of the sets A dan B

A  B the intersection of the sets A dan B
a  A the element a belongs to the set A

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