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Set of ordered pairs 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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Question

Set of ordered pair of a function ? If so, examine whether the mapping is injective or surjective :{(ab) : a is a person, b is an ancestor of a

Sum
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Solution

g = {(a, b) : a is a person, b is an ancestor of a}
Since, the ordered map (ab) does not map 'a' - a person to a living person.
So, g is not a function.

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Chapter 2: Functions - Exercise 2.1 [Page 32]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.1 | Q 9.2 | Page 32

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