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Question
Are the following set of ordered pairs functions? If so, examine whether the mapping is injective or surjective.
{(x, y): x is a person, y is the mother of x}
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Solution
Given, {(x, y): x is a person, y is the mother of x}
It’s clearly seen that each person ‘x’ has only one biological mother.
Hence, the above set of ordered pairs make a function.
Now more than one person may have same mother.
Thus, the function is many-many one and surjective.
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