Question
Let A = {1, 2, 3, 4, 5, 6}. Let R be a relation on A defined by
{(a, b) : a, b ∈ A, b is exactly divisible by a}
  1. Writer R in roster form.
  2. Find the domain of R.
  3. Find the range of R.

Answer

We have,
A = {1, 2, 3, 4, 5, 6}
and, {(a, b): a, b ∈ A, b is exactly divisible by a}
  1. Now, $\frac{\text{a}}{\text{b}}$ stands for 'a divides b'. For the elements of the given sets A and A, we find that,
$\frac{1}{1},\frac{1}{2},\frac{1}{3},\frac{1}{4},\frac{1}{5},\frac{1}{6},\frac{2}{2},\frac{2}{4},\frac{2}{6},\frac{3}{3},\frac{3}{6},\frac{4}{4},\frac{5}{5},\frac{6}{6}$

$\therefore$ Relation R in roster form is

R = {(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 2), (2, 4), (2, 6), (3, 3), (3, 6), (4, 4), (5, 5), (6, 6)}
  1. Domain(R) = {1, 2, 3, 4, 5, 6}
  2. Range(R) = {1, 2, 3, 4, 5, 6}

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free