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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 (A) 720

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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

MCQ
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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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Chapter 2: Functions - Exercise 2.6 [Page 79]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.6 | Q 53 | Page 79

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