# Thread: how to solve these two problems??

1. ## how to solve these two problems??

Q-1. Let R be the relation on the set A = {1, 2, 3, 4} defined by aRb if and only if 2a > b + 1.
a) List the ordered pairs in R.
b) Find the matrix representing R.

Q-7. Suppose that the relation R is defined on the set Z where aRb means a = ±b. Establish whether R is an equivalence relation giving your justifications.

2. ## Re: how to solve these two problems??

Originally Posted by mehdi98
Q-1. Let R be the relation on the set A = {1, 2, 3, 4} defined by aRb if and only if 2a > b + 1.
a) List the ordered pairs in R.
b) Find the matrix representing R.
Q-7. Suppose that the relation R is defined on the set Z where aRb means a = ±b. Establish whether R is an equivalence relation giving your justifications.
QI. a) $\{(2,1),(3,2)\cdots\}\subset\mathcal{R}$ you such fillout the other members.
b) $\begin{array}{*{20}{c}} {}&1&2&3&4 \\ \hline {1|}&X&0&0&0 \\ {2|}&X&X&0&0 \\ {3|}&X&{}&{}&{} \\ {4|}&{}&{}&{}&{} \end{array}$ you need to use the correct symbols and complete the matrix.