High school mathematics compulsory one

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Content related to other numbers in Mathematics

• prime number （ Prime number ）

Prime Numbers are also called prime Numbers , Its own meaning refers to , In the set of positive integers (N+/N*) in , remove 1 And numbers other than itself ,
It cannot have other factors , That is, it cannot be divided by other numbers .

• Sum （ The opposite of prime ）

In a set of positive integers , It removes natural numbers 1 And beyond itself , A number that can still be divided by other positive integers , It's called composite number .

• 0

0 Not a positive integer , Nor is it a negative integer . But it is a natural number .

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1. aggregate

1.1 The basic concept of set

Related concepts of elements and sets

1. Elements : General , hold （ Subjects of study ） Collectively referred to as element , Latin letters often used in lowercase （a,b,c…） Express .
2. aggregate ： some （ Elements ） Make up the whole , abbreviation （ Set / aggregate ）, It is often expressed in capital Latin letters （A,B,C…）.
3. Set equal ： The elements that make up the two are （ equally ） Of .
4. Characteristics of elements in the set ： （ The opposite sex ）（ deterministic ） and （ Disorder ）;

• If ( Elements )a yes ( aggregate )A The elements of , Just say a Belong to （belong to） aggregate A, Write it down as I can't type this symbol .
• If a No A The elements in , Just say a Do not belong to （not belong to） aggregate A, Remember, I still can't type this symbol .

Some commonly used number sets and their notation in Mathematics

1. All of you Non-negative integer The set formed is called Nonnegative integer set （ Or set of natural numbers ）, Write it down as N.

What is a nonnegative integer , Non negative integers are integers that do not contain negative numbers , Now the textbook has 0 Included in the set of nonnegative integers . in other words
As long as this number x >= 0 It is a nonnegative integer , It can also be called natural number .

2. be-all Positive integer The set formed is called Positive integer set , Write it down as N* perhaps N+;

3. All of you Integers The set formed is called Set of integers , Write it down as Z;

4. All of you Rational number The set formed is called Set of rational numbers , Write it down as Q;

5. All of you The set of real Numbers The set formed is called Set of real numbers , Write it down as R;

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