Math Problem Statement

Rezolva

Se dau mulțimile A = {x | x ∈ R și -3 < x ≤ 1} și B = {y | y ∈ R și -2 ≤ y < 3}. Din mulțimile A, B, A ∪ B, A ∩ B, B - A, Alegeți: a) mulțimile care se pot scrie ca interval și reprezentați-le pe axa reală; b) mulțimile finite și scrieți-le prin enumerarea elementelor.

Solution

To solve this problem, let's first interpret the mathematical sets and the task:

The problem defines two sets:

  • A={xR3<x1}A = \{x \in \mathbb{R} \mid -3 < x \leq 1 \}
  • B={yR2y<3}B = \{ y \in \mathbb{R} \mid -2 \leq y < 3 \}

You are asked to work with the following set operations:

  1. ABA \cap B (the intersection of sets A and B)
  2. ABA \cup B (the union of sets A and B)
  3. BAB - A (the difference between sets B and A)

Let’s compute each:

1. ABA \cap B (Intersection of AA and BB):

The intersection consists of the elements common to both sets.

  • Set AA is the interval (3,1](-3, 1].
  • Set BB is the interval [2,3)[-2, 3).

So, the intersection ABA \cap B would be the overlapping region between these two intervals:

  • AB=[2,1]A \cap B = [-2, 1]

2. ABA \cup B (Union of AA and BB):

The union consists of all elements that are in either set.

  • Union of the intervals (3,1](-3, 1] and [2,3)[-2, 3) covers from 3-3 to 33.

Thus, AB=(3,3)A \cup B = (-3, 3).

3. BAB - A (Difference BB minus AA):

This represents the elements that are in set BB but not in set AA.

  • B=[2,3)B = [-2, 3)
  • A=(3,1]A = (-3, 1]

The difference BAB - A includes the part of BB that is not in AA, which is (1,3)(1, 3).

Final answers:

  • AB=[2,1]A \cap B = [-2, 1]
  • AB=(3,3)A \cup B = (-3, 3)
  • BA=(1,3)B - A = (1, 3)

Let me know if you'd like further clarification or details on any of these operations. Here are 5 related questions you might want to explore next:

  1. What is the meaning of the symmetric difference between two sets?
  2. How can we represent these intervals on the real number line?
  3. What changes if one or both of the intervals are open or closed?
  4. Can we express the sets AA and BB using set-builder notation differently?
  5. How do we calculate the cardinality of finite sets?

Tip: In set theory, the intersection is always a subset of both sets, while the union includes all elements from both.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Set Theory
Intervals
Intersection of Sets
Union of Sets
Set Difference

Formulas

A = {x ∈ R | -3 < x ≤ 1}
B = {y ∈ R | -2 ≤ y < 3}
A ∩ B (Intersection): {x ∈ A ∧ x ∈ B}
A ∪ B (Union): {x ∈ A ∨ x ∈ B}
B - A (Difference): {x ∈ B ∧ x ∉ A}

Theorems

Properties of set operations: intersection, union, and difference.

Suitable Grade Level

High School (Grades 9-12)