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प्रश्न
Set of ordered pair of a function ? If so, examine whether the mapping is injective or surjective :{(a, b) : a is a person, b is an ancestor of a}
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उत्तर
g = {(a, b) : a is a person, b is an ancestor of a}
Since, the ordered map (a, b) does not map 'a' - a person to a living person.
So, g is not a function.
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