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Question
R is a relation from {11, 12, 13} to {8, 10, 12} defined by y = x − 3. Then, R−1 is ______________ .
Options
{(8, 11), (10, 13)}
{(11, 8), (13, 10)}
{(10, 13), (8, 11)}
none of these
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Solution
{(8, 11), (10, 13)}
The relation R is defined by
R= {(x, y) : x ∈ {11, 12, 13}, y ∈ {8, 10, 12} : y = x−3}
⇒ R = { (11, 8), (13, 10) }
So, R−1={ (8, 11), (10, 13) }
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