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Question
Are the following set of ordered pairs functions? 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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Solution
Given, {(a, b): a is a person, b is an ancestor of a}
It’s clearly seen that any person ‘a’ has more than one ancestors.
Thus, it does not represent a function.
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