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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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प्रश्न

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}

योग
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उत्तर

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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अध्याय 1: Relations And Functions - Exercise [पृष्ठ ११]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 1 Relations And Functions
Exercise | Q 8. (i) | पृष्ठ ११

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