Math Problem Statement

Write the relation R as a table, where the relation R on {1,2,3,4} defined by (x,y) ∈ R if x squared greater or equal than y.

Solution

To write the relation RR as a table where (x,y)R(x, y) \in R if and only if x2yx^2 \geq y, let's first understand the condition:

The set A={1,2,3,4}A = \{1, 2, 3, 4\} represents the elements involved in the relation. The relation condition states that for each pair (x,y)(x, y), x2yx^2 \geq y must hold true. This means for each value of xx, we need to check whether x2x^2 is greater than or equal to yy, for all y{1,2,3,4}y \in \{1, 2, 3, 4\}.

Let’s calculate x2x^2 for each x{1,2,3,4}x \in \{1, 2, 3, 4\}:

  • For x=1x = 1, 12=11^2 = 1
  • For x=2x = 2, 22=42^2 = 4
  • For x=3x = 3, 32=93^2 = 9
  • For x=4x = 4, 42=164^2 = 16

Now, for each xx, check if x2yx^2 \geq y:

  1. For x=1x = 1:

    • 1211^2 \geq 1, true (so (1,1)(1, 1) is in RR)
    • 1221^2 \geq 2, false
    • 1231^2 \geq 3, false
    • 1241^2 \geq 4, false

    So, the pairs for x=1x = 1 are (1,1)(1, 1).

  2. For x=2x = 2:

    • 2212^2 \geq 1, true (so (2,1)(2, 1) is in RR)
    • 2222^2 \geq 2, true (so (2,2)(2, 2) is in RR)
    • 2232^2 \geq 3, true (so (2,3)(2, 3) is in RR)
    • 2242^2 \geq 4, true (so (2,4)(2, 4) is in RR)

    So, the pairs for x=2x = 2 are (2,1),(2,2),(2,3),(2,4)(2, 1), (2, 2), (2, 3), (2, 4).

  3. For x=3x = 3:

    • 3213^2 \geq 1, true (so (3,1)(3, 1) is in RR)
    • 3223^2 \geq 2, true (so (3,2)(3, 2) is in RR)
    • 3233^2 \geq 3, true (so (3,3)(3, 3) is in RR)
    • 3243^2 \geq 4, true (so (3,4)(3, 4) is in RR)

    So, the pairs for x=3x = 3 are (3,1),(3,2),(3,3),(3,4)(3, 1), (3, 2), (3, 3), (3, 4).

  4. For x=4x = 4:

    • 4214^2 \geq 1, true (so (4,1)(4, 1) is in RR)
    • 4224^2 \geq 2, true (so (4,2)(4, 2) is in RR)
    • 4234^2 \geq 3, true (so (4,3)(4, 3) is in RR)
    • 4244^2 \geq 4, true (so (4,4)(4, 4) is in RR)

    So, the pairs for x=4x = 4 are (4,1),(4,2),(4,3),(4,4)(4, 1), (4, 2), (4, 3), (4, 4).

Now, let's put this information into a table format. The relation RR is:

x \ y1234
1
2
3
4

Where "✓" indicates that (x,y)R(x, y) \in R.


Would you like further details or clarifications on any part? Here are a few related questions to explore:

  1. How can you describe the properties of the relation RR?
  2. What happens if we change the condition to x2<yx^2 < y?
  3. How can you represent a relation using set notation?
  4. Can a relation be symmetric in this case? Why or why not?
  5. How can you test if a relation is transitive using this table?

Tip: For relations, the table format can be very useful for visualizing which pairs satisfy the given condition!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Relations
Set Theory
Inequalities

Formulas

x^2 ≥ y

Theorems

Properties of Relations

Suitable Grade Level

Grades 9-12