Question:
If the set $A$ contains $5$ elements and the set $B$ contains $6$ elements, then the number of one-one and onto mappings from $A$ to $B$ is
If the set $A$ contains $5$ elements and the set $B$ contains $6$ elements, then the number of one-one and onto mappings from $A$ to $B$ is
Updated On: Jul 6, 2022
- $720$
- $120$
- $0$
- none of these
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The Correct Option is C
Solution and Explanation
As A contains $5$ elements.
$\therefore$ For any one-one onto mapping $f$ : $A \to B$, $f (A)$ also contains $5$ elements but $B$ contains $6$ elements.
$\therefore f (A) \ne B$.
So, no one-one mapping from $A$ to $B$ can be onto.
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