1. (Numbers)
How many numbers in the interval [1431,9758] are
a. divisible by 3?
b. divisible by 5?
c. divisible by 3 and 5?
d. divisible by 3 or 5?
2. (Sets)
Prove that
a. using Venn diagrams,
b. without Venn diagrams.
4. (Propositional Logic)
For each of the following formulae, determine all the truth assignments to , and under which
5. (Proving properties of algorithms)
Recall the algorithm for computing the greatest common divisor (gcd) of two positive numbers:
1 of 2 17/02/2020, 4:18 pm COMP9020 20T1 - Week 1 Problem Set https://cgi.cse.unsw.edu.au/~cs9020/20T1/probs/prob1/index.php
Recall the correctness proof given in class. What needs to be changed to adapt it to the faster version below?
6. Challenge Exercise
A multiplication magic square has the product of the numbers in each row, column and diagonal the same. If the diagram below is filled with positive integers to form a multiplicative magic square, then give the value of y.
5
y
4
1
