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Question
Mark the correct alternative in the following 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
Options
720
120
0
none of these
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Solution
\[\text{As, the number of bijection from A into B can only be possible when provided n}\left( A \right) \geq n\left( B \right)\]
\[\text{But here n}\left( A \right) < n\left( B \right)\]
\[\text{So, the number of bijection i . e . one - one and onto mappings from A to B} = 0\]
Hence, the correct alternative is option (c).
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