मराठी

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

Set of ordered pair of  a function? If so, examine whether the mapping is injective or surjective :{(xy) : x is a person, y is the mother of x}

बेरीज
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उत्तर

 f = {(xy) : x is a person, y is the mother of x}

As, for each element x in domain set, there is a unique related element y in co-domain set.

So, f is the function.

Injection test:
As, y can be mother of two or more persons
So, f is not injective.

Surjection test :

For every mother y defined by (xy), there exists a person x for whom y is mother.
So, f is surjective.
Therefore, f is surjective function.

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पाठ 2: Functions - Exercise 2.1 [पृष्ठ ३२]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 2 Functions
Exercise 2.1 | Q 9.1 | पृष्ठ ३२

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