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Statement -1: The expression n!(20-n)! i...

Statement -1: The expression `n!(20-n)!` is minimum when `n=10`.
because
Statement -2: `.^(2p)C_(r)` is maximum when `r=p`.

A

Statement -1 is True, Statement-2 is True, Statement -2 is a correct explanation for Statement -1

B

Statement -1 is True, Statement -2 is True, Statemetn -2 is NOT a correct explanation for Statement -1.

C

Statement -1 is True, Statement -2 is False.

D

Statement -1 is False, Statement -2 is True

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze both statements and determine their validity step by step. ### Step 1: Analyze Statement 1 **Statement 1**: The expression \( n!(20-n)! \) is minimum when \( n=10 \). 1. **Understanding the Expression**: The expression \( n!(20-n)! \) represents the product of the factorial of \( n \) and the factorial of \( 20-n \). 2. **Using Combinatorial Identity**: We can relate this expression to combinations: \[ n!(20-n)! = \frac{20!}{20Cn} \] where \( 20Cn \) is the number of ways to choose \( n \) items from 20. 3. **Finding Minimum**: The expression \( n!(20-n)! \) will be minimized when \( 20Cn \) is maximized. From combinatorial principles, \( 20Cn \) is maximized when \( n \) is around \( \frac{20}{2} = 10 \). 4. **Conclusion for Statement 1**: Therefore, Statement 1 is true because \( n!(20-n)! \) is indeed minimum when \( n=10 \). ### Step 2: Analyze Statement 2 **Statement 2**: \( 2pC_r \) is maximum when \( r=p \). 1. **Understanding the Expression**: The expression \( 2pC_r \) represents the number of ways to choose \( r \) items from \( 2p \). 2. **Finding Maximum**: The binomial coefficient \( 2pC_r \) reaches its maximum value when \( r \) is equal to \( p \) (or close to \( p \)), as this is a property of binomial coefficients. 3. **Conclusion for Statement 2**: Thus, Statement 2 is also true because \( 2pC_r \) is maximized when \( r=p \). ### Step 3: Relationship Between Statements - Since both statements are true, we need to check if Statement 2 provides a correct explanation for Statement 1. - We see that both statements relate to maximizing and minimizing expressions involving factorials and combinations. ### Final Conclusion Both statements are true, and Statement 2 correctly explains why Statement 1 is true. Therefore, the correct option is that both statements are true, and Statement 2 is a correct explanation for Statement 1.
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