Practice Definition (4.1) - Relations and Functions

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6 sample questions

Question 1.
Define a relation.
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Focus on how elements from two sets interact.
Question 2.
What is a reflexive relation?
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Think of self-pairs.
3Question 3.
What defines a reflexive relation?
- A relation with unique pairs.
- A relation consisting of (x, x) for all elements.
- A relation with only symmetrical pairs.
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Reflect on self-connections in sets.
4Question 4.
True or False: Every bijective function is also surjective.
- True
- False
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Consider the definitions of surjective and injective together.
Question 5.
Create a function from set A = {1, 2, 3, 4} to set B = {x, y}. Can such a function be injective? Explain why or why not.
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Consider uniqueness in mappings.
Question 6.
Consider sets A = {1, 2} and B = {a, b, c}. Define a function from A to B and evaluate its surjectiveness.
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Check the coverage of outputs.

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