Are the following set of ordered pairs functions?
If so examine whether the mapping is injective or surjective.
(i) $\{ (x,y):x$ is a person, $y$ is the mother of $x\}$.
(ii) $\{ (a,b):a$ is a person, $b$ is an ancestor of $a\}$.
Relations and Functions — Class 12 Maths Solution
Step-by-step Solution
(i) Given set of ordered pair is $\{ (x,y):x$ is
a person, $y$ is the mother of $x\}$.
It represent a function. Here, the image of
distinct elements of $x$ under $f$ are not
distinct, so it is not a injective but it is a
surjective.
(ii) Set of ordered pairs $= \{ (a,b):a$ is a person, $b$ is an ancestor of $a\}$
Here, each element of domain does not have a
unique image. So, it does not represent function.
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