Practice Functions (24.1) - Functions - Discrete Mathematics

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6 sample questions

Question 1.
What is a function?
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Think about how every input value relates uniquely to an output.
Question 2.
Define injective function.
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Focus on the unique output for each input!
3Question 3.
What is the definition of a bijective function?
- A function that is neither injective nor surjective
- A function that is both injective and surjective
- A function that is only injective
- A function that maps only some elements from A to B
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Think about the definitions of injective and surjective.
4Question 4.
True or False: Every injective function is surjective.
- True
- False
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Reflect on the definitions of both types of functions.
Question 5.
Prove that the function f(n) = 3n + 2 is bijective.
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Consider how to invert the function.
Question 6.
If f and g are functions such that f: A → B and g: B → C, create a composite function and explain its significance.
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Think about what it means to apply one function after the other.

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