# Solving discrete math problems

1) Use Venn diagrams to determine whether each of the following is true or false:

a. (A union B) intersect C = A union (B intersect C)

b. A intersect (B union C) = (A intersect B) union (A intersect C)

2) Calculate the number of integers divisible by 4 between 50 and 500, inclusive.

3) Use the permutation formula to calculate the number permutations of the set {a, b, c, d} taken two at a time. Also list these permutations.

4) Determine whether each of the following functions is 1-to-1 and whether it is onto. Assume the domain and co-domain is Z, the integers. Explain your answers.

a. f(n) = n / 2, assuming integer division

b. g(n) = 4n + 5

https://brainmass.com/math/discrete-structures/solving-discrete-math-problems-605089

#### Solution Preview

Please check attachment for solution.

1) Use Venn diagrams to determine whether each of the following is true or false:

a. (A union B) intersect C = A union (B intersect C)

For (A union B) intersect C, the diagram is shown below (area with line is our target area):

(see attached file for diagram)

For A union (B intersect C), the diagram is shown below (area with line is our target area):

(see attached file for diagram)

It is obvious that two areas are not equal. ...

#### Solution Summary

The solution gives detailed steps on solving a set of questions on discrete math: venn diagram, permutation, 1-to-1 relation and onto relation.