Chapter 1: Concepts of Sets and ns
XXX Sets
1.Meaning of Sets: A set is the n of XXX to this whole。The objects under study are called elements。and the n of some elements is called a set。abbreviated as a set.
2.Three characteristics of the XXX:
1) n of elements: If a set is determined。then it is certain whether an element belongs to this set or not.
2) Distinctiveness of elements: XXX elements in a given set are unique and cannot be repeated.
3) Unorderedness of elements: The n of elements in a set can be changed。and changing their n does not affect the set.
3.n of Sets: {。}
1) XXX: A = {members of our school's basketball team}。B = {1,2,3,4,5}.
龙梅子的资料2) Methods of representing sets: listing method and n method.
a。Listing method: List all the elements in the set one by one {a。b。c。}.
b。n method:
① Interval method: Describe the common properties of the elements in the set and write them in curly braces to represent the set.
x∈R|x-3>2}。{x|x-3>2}
② Language n method: XXX: {triangles that are not right triangles}.
③ Venn diagram: Draw a closed curve。with the curve representing the set.
4.n of Sets:
1) Finite set: A XXX.
2) Infinite set: A XXX.
3) Empty set: A set that XXX.
5.nship een XXX:
1) If an element is in a set。then the element belongs to the set。that is: a∈A.
我在北京挺好的演员表2) If an element is not in a set。then the element does not belong to the set。that is: a￠A.
Note: XXX:任晓妍
Non-negative integer set (i.e。natural number set) is denoted as: N.
Positive integer XXX.
可卸光疗甲Integer set Z.
nal number set Q.
Real number set R.
6.XXX Sets
1) "n" nship (1) - Subset
高一数学必修1n: If every element of set A is an element of set B。we say that sets A and B have an n nship。and set A is a subset of set B。n: A⊆B (or B⊇A).
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