Question

Let R be a relation on N defined by x + 2y = 8. The domain of R is

• A. {2, 4, 8}
• B. {2, 4, 6, 8}
• C. {2, 4, 6}
• D. {1, 2, 3, 4}

Answer 1

The correct option is C

{2, 4, 6}

x + 2y = 8

$\Rightarrow x=8-2y$

For y = 1, x = 6

y = 2, x = 4

y = 3, x = 2

Then R = {(2, 3), (4, 2), (6, 1)}

$\therefore$ Domain of R = {2, 4, 6}