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S(1)= sum(j=1)^(10) j (j -1)""^(10)C(j) ...


`S_(1)= sum_(j=1)^(10) j (j -1)""^(10)C_(j) and S_(2)= sum_(j=1)^(10)j.""^(10)C_(j) .` Statement-1 `S_(3) = 50xx2^(9)`.
Statement-2 `S_(1) = 90xx2^(8) and S_(2) = 10 xx 2^(8)`

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To solve the problem, we need to evaluate the sums \( S_1 \) and \( S_2 \) and check the validity of the statements provided. ### Step 1: Evaluate \( S_2 \) We start with the expression for \( S_2 \): \[ S_2 = \sum_{j=1}^{10} j \cdot \binom{10}{j} \] Using the identity \( j \cdot \binom{n}{j} = n \cdot \binom{n-1}{j-1} \), we can rewrite \( S_2 \): \[ S_2 = 10 \cdot \sum_{j=1}^{10} \binom{9}{j-1} \] Now, we can change the index of summation by letting \( k = j - 1 \): \[ S_2 = 10 \cdot \sum_{k=0}^{9} \binom{9}{k} = 10 \cdot 2^9 \] Thus, we have: \[ S_2 = 10 \cdot 2^9 \] ### Step 2: Evaluate \( S_1 \) Now we evaluate \( S_1 \): \[ S_1 = \sum_{j=1}^{10} j(j-1) \cdot \binom{10}{j} \] Using the identity \( j(j-1) \cdot \binom{n}{j} = n(n-1) \cdot \binom{n-2}{j-2} \), we can rewrite \( S_1 \): \[ S_1 = 10 \cdot 9 \cdot \sum_{j=2}^{10} \binom{8}{j-2} \] Changing the index of summation by letting \( k = j - 2 \): \[ S_1 = 90 \cdot \sum_{k=0}^{8} \binom{8}{k} = 90 \cdot 2^8 \] Thus, we have: \[ S_1 = 90 \cdot 2^8 \] ### Step 3: Evaluate \( S_3 \) Now we evaluate \( S_3 \): \[ S_3 = \sum_{j=1}^{10} j \cdot 2 \cdot \binom{10}{j} \] This can be expressed as: \[ S_3 = 2 \cdot \sum_{j=1}^{10} j \cdot \binom{10}{j} = 2 \cdot S_2 \] Using the value of \( S_2 \): \[ S_3 = 2 \cdot (10 \cdot 2^9) = 20 \cdot 2^9 \] ### Conclusion Now we have: - \( S_1 = 90 \cdot 2^8 \) - \( S_2 = 10 \cdot 2^9 \) - \( S_3 = 20 \cdot 2^9 \) ### Verification of Statements **Statement 1:** \( S_3 = 50 \cdot 2^9 \) is **False** (it should be \( 20 \cdot 2^9 \)). **Statement 2:** \( S_1 = 90 \cdot 2^8 \) and \( S_2 = 10 \cdot 2^8 \) is **False** (it should be \( S_2 = 10 \cdot 2^9 \)).

To solve the problem, we need to evaluate the sums \( S_1 \) and \( S_2 \) and check the validity of the statements provided. ### Step 1: Evaluate \( S_2 \) We start with the expression for \( S_2 \): \[ S_2 = \sum_{j=1}^{10} j \cdot \binom{10}{j} \] ...
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Let S_(1) = sum_(j=1)^(10) j(j-1).""^(10)C_(j), S_(2) = sum_(j=1)^(10)j.""^(10)C_(j) , and S_(3) = sum_(j=1)^(10) j^(2).""^(10)C_(j) . Statement 1 : S_(3) = 55 xx 2^(9) . Statement 2 : S_(1) = 90 xx 2^(8) and S_(2) = 10 xx 2^(8) .

Let S_1=sum_(j=1)^(10)j(j-1)^(10)C_j ,""S_2=sum_(j=1)^(10)j""^(10)C_j and S_3=sum_(j=1)^(10)j^2""^("10")"C"_"j"dot Statement-1: S_3=""55xx2^9 Statement-2: S_1=""90xx2^8a n d""S_2=""10xx2^8 . (1) Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation for Statement-1 (2) Statement-1 is true, Statement-2 is false (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1

Let S_1=sum_(j=1)^(10)j(j-1)^(10)C_j ,""S_2=sum_(j=1)^(10)j""^(10)C_i "andS"_"3"=sum_(j=1)^(10)j^2""^("10")"C"_"j"dot Statement-1: S_3=""55xx2^9 Statement-2: S_1=""90xx2^8a n d""S_2=""10xx2^8 . (1) Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation for Statement-1 (2) Statement-1 is true, Statement-2 is false (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1

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