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Question
Represent the given relation by
(a) an arrow diagram
(b) a graph and
(c) a set in roster form, wherever possible
{(x, y) | x = 2y, x ∈ {2, 3, 4, 5}, y ∈ {1, 2, 3, 4}
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Solution
x = {2, 3, 4, 5} y = {1, 2, 3, 4}
x = 2y
2y = x
y = `x/2`
If `x = 2 ⇒ y = x/2 = 2/2 = 1`
if `x = 3 ⇒ y = x/2 = 3/2`
If `x = 4 ⇒ y = x/2 = 4/2 = 2`
If `x = 5 ⇒ y = x/2 = 5/2`
(a) Arrow diagram

(b) Graph

(c) Roster form R = {(2, 1) (4, 2)}
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