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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 the two statements given and determine their validity. ### Step 1: Analyze Statement 1 **Statement 1:** The expression \( n!(20-n)! \) is minimum when \( n=10 \). To analyze this, we can rewrite the expression in terms of combinations: \[ \binom{20}{n} = \frac{20!}{n!(20-n)!} \] Thus, we can express \( n!(20-n)! \) as: \[ n!(20-n)! = \frac{20!}{\binom{20}{n}} \] This means that \( n!(20-n)! \) is minimized when \( \binom{20}{n} \) is maximized. ### Step 2: Find the Maximum of \( \binom{20}{n} \) The binomial coefficient \( \binom{20}{n} \) reaches its maximum when \( n \) is around \( \frac{20}{2} = 10 \). This is a well-known property of binomial coefficients, where they are symmetric and peak at the middle values. ### Step 3: Conclusion for Statement 1 Since \( \binom{20}{n} \) is maximized at \( n = 10 \), it follows that \( n!(20-n)! \) is minimized at \( n = 10 \). Therefore, **Statement 1 is true**. ### Step 4: Analyze Statement 2 **Statement 2:** \( \binom{2p}{r} \) is maximum when \( r=p \). This is also a known property of binomial coefficients. The binomial coefficient \( \binom{n}{k} \) is maximized when \( k \) is approximately \( \frac{n}{2} \). Therefore, for \( n = 2p \), it is maximized when \( r = p \). ### Step 5: Conclusion for Statement 2 Since \( \binom{2p}{r} \) is indeed maximized at \( r = p \), **Statement 2 is true**. ### Final Conclusion Both statements are true. However, Statement 2 does not serve as a correct explanation for Statement 1, as they pertain to different contexts. Thus, the answer is: **Option A:** Statement 1 is true, Statement 2 is true, but Statement 2 is not a correct explanation of Statement 1. ---
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