Practice Part (b): Composition Of Functions (2.6.2) - Introduction - Discrete Mathematics

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6 sample questions

Question 1.
What is a surjective function? Give an example.
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Think about functions that cover all outputs.
Question 2.
How does an injective function differ from a surjective function?
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Consider how functions can map inputs to outputs.
3Question 3.
What is true about a surjective function?
- All elements in the domain are mapped to unique elements.
- Every element in the codomain is covered.
- It cannot have repeated outputs.
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Focus on what it means when every output has a backing input.
4Question 4.
A function can be surjective in finite sets. True or False?
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Recall the definition of surjectivity in context.
Question 5.
Imagine a function f: {1, 2, 3, 4} → {a, b, c} is defined. What can you conclude about its surjectivity and injectivity?
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Reflect on the cardinality principle in set functions.
Question 6.
Define a surjective function from the set of all integers to a set containing two elements. Provide justification for your answer.
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Consider how to classify integers into distinct categories.

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