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Statement-1: sum(r=0)^(n) (1)/(r+1) ""^(...

Statement-1: `sum_(r=0)^(n) (1)/(r+1) ""^(n)C_(r) = (1)/((n+1)x) {( 1 + x)^(n+1) -1}^(-1)`
Statement-2: ` sum_(r=0)^(n) (""^(n)C_(r))/(r+1) = (2^(n+1))/(n+1)`.

A

1

B

2

C

3

D

4

Text Solution

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The correct Answer is:
To solve the given problem, we need to analyze both statements and verify their validity step by step. ### Step 1: Analyze Statement 1 We start with the first statement: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \frac{1}{(n+1)x} \left( (1+x)^{n+1} - 1 \right)^{-1} \] #### Step 1.1: Rewrite the left-hand side The term \(\binom{n}{r}\) can be expressed as: \[ \binom{n}{r} = \frac{n!}{r!(n-r)!} \] Thus, we can rewrite the left-hand side: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \sum_{r=0}^{n} \frac{n!}{(r+1)!(n-r)!} \] This can be simplified by noting that: \[ \frac{1}{r+1} \binom{n}{r} = \frac{1}{n+1} \binom{n+1}{r+1} \] Therefore, we can rewrite the sum as: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \frac{1}{n+1} \sum_{r=1}^{n+1} \binom{n+1}{r} \] #### Step 1.2: Evaluate the sum The sum \(\sum_{r=1}^{n+1} \binom{n+1}{r}\) equals \(2^{n+1} - 1\) (since it includes all terms except for \(r=0\)). Thus, we have: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \frac{1}{n+1} (2^{n+1} - 1) \] ### Step 2: Compare with the right-hand side Now we need to check if this matches the right-hand side: \[ \frac{1}{(n+1)x} \left( (1+x)^{n+1} - 1 \right)^{-1} \] Substituting \(x = 1\): \[ \frac{1}{(n+1)} \left( 2^{n+1} - 1 \right) \] This confirms that Statement 1 is true. ### Step 3: Analyze Statement 2 Now we check the second statement: \[ \sum_{r=0}^{n} \frac{\binom{n}{r}}{r+1} = \frac{2^{n+1}}{n+1} \] #### Step 3.1: Use the result from Statement 1 From our previous result, we found: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \frac{2^{n+1} - 1}{n+1} \] This means that: \[ \sum_{r=0}^{n} \frac{\binom{n}{r}}{r+1} = \frac{2^{n+1} - 1}{n+1} \] #### Step 3.2: Compare with the right-hand side The right-hand side of Statement 2 is: \[ \frac{2^{n+1}}{n+1} \] Since \(\frac{2^{n+1} - 1}{n+1} \neq \frac{2^{n+1}}{n+1}\), we conclude that Statement 2 is false. ### Conclusion - Statement 1 is **True**. - Statement 2 is **False**.

To solve the given problem, we need to analyze both statements and verify their validity step by step. ### Step 1: Analyze Statement 1 We start with the first statement: \[ \sum_{r=0}^{n} \frac{1}{r+1} \binom{n}{r} = \frac{1}{(n+1)x} \left( (1+x)^{n+1} - 1 \right)^{-1} \] ...
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