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Mark the Correct Alternative in the Following Question: If the Set a Contains 7 Elements and the Set B Contains 10 Elements, Then the Number One-one Functions from a to B is (A) 10c7 (B) 10c7 × - Mathematics

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Question

Mark the correct alternative in the following question:
If the set A contains 7 elements and the set B contains 10 elements, then the number one-one functions from A to B is

Options

  • 10C7 

  • 10C7\[\times\] 7!

  • 710 

  • 107

MCQ

Solution

As, the number of one-one functions from A to B with m and n elements, respectively = nPm = nCm

\[\times\] m! 

So, the number of one-one functions from A to B with 7 and 10 elements, respectively = 10P7 = 10C7 \[\times\]7! 

Hence, the correct alternative is option (b).

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Chapter 2: Functions - Exercise 2.6 [Page 79]

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RD Sharma Mathematics [English] Class 12
Chapter 2 Functions
Exercise 2.6 | Q 54 | Page 79

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