Practice Primality Testing (1.3) - Prime Numbers and GCD - Discrete Mathematics

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6 sample questions

Question 1.
Define a prime number.
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Think about what factors a number can have.
Question 2.
Is 4 a prime number? Why or why not?
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Remember the definition of a prime number!
3Question 3.
What defines a prime number?
- Only divisible by 1 and itself
- Divisible by multiple numbers
- Equal to 1
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Recall the definition discussed.
4Question 4.
True or False: The GCD of 20 and 30 is 10.
- True
- False
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Think about the factors of each number.
Question 5.
Determine if 103 is a prime number using the naive testing algorithm. Demonstrate your process.
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Remember to make your checks only go up to the square root.
Question 6.
Explain how changing the input number affects the running time of the naive primality test.
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Consider how each added bit may relate to the number of checks required.

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