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Statement 1 : The sum of the series 1...

Statement 1 :
The sum of the series 1+(1+2+4)+(4+6+9)+(9+12+16)+….+(361 +380 +400) is 8000
Statement 1:
`Sigma_(k=1)^(n) (k^3-(k-1)^3)=n^3`, for any natural number n.

A

Statement 1 is fasle ,statement 2 is true

B

Statement 1 is true ,statement 2 is true , statement 2 is a correct explanation for statement 1.

C

Statement 1 is true, statements 2 is true statement 2 is not a correct explanation for statement 1

D

Statement 1 is true, statement 2 is false

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The correct Answer is:
To solve the problem, we need to analyze the two statements provided: **Statement 1**: The sum of the series \(1 + (1 + 2 + 4) + (4 + 6 + 9) + (9 + 12 + 16) + \ldots + (361 + 380 + 400)\) is 8000. **Statement 2**: \(\Sigma_{k=1}^{n} (k^3 - (k-1)^3) = n^3\) for any natural number \(n\). ### Step-by-Step Solution **Step 1: Understand the Series in Statement 1** The series given in Statement 1 can be broken down into groups: - The first group is \(1\). - The second group is \(1 + 2 + 4\). - The third group is \(4 + 6 + 9\). - The fourth group is \(9 + 12 + 16\). - The last group is \(361 + 380 + 400\). We need to identify a pattern in these groups. **Hint for Step 1**: Look for a pattern in how the numbers are grouped and how they progress. **Step 2: Identify the Pattern** The first term is \(1\), the second group sums to \(7\) (which is \(1 + 2 + 4\)), the third group sums to \(19\) (which is \(4 + 6 + 9\)), and so on. Notice that each group seems to consist of consecutive perfect squares: - The first group has \(1^2\). - The second group has \(1^2 + 2^2\). - The third group has \(2^2 + 3^2\). - The fourth group has \(3^2 + 4^2\). - The last group has \(19^2 + 20^2\). **Hint for Step 2**: Try to express each group in terms of squares or cubes. **Step 3: Calculate the Sum of Each Group** We can calculate the sum of each group: - First group: \(1 = 1\) - Second group: \(1 + 2 + 4 = 7\) - Third group: \(4 + 6 + 9 = 19\) - Fourth group: \(9 + 12 + 16 = 37\) - Last group: \(361 + 380 + 400 = 1141\) Now, we need to sum these results. **Hint for Step 3**: Add the results of each group carefully. **Step 4: Calculate the Total Sum** Now, let's sum the values: \[ 1 + 7 + 19 + 37 + 1141 = 1205 \] This does not equal 8000, indicating that Statement 1 is false. **Hint for Step 4**: Ensure you add all the groups correctly and check your calculations. **Step 5: Analyze Statement 2** For Statement 2, we can use the identity: \[ k^3 - (k-1)^3 = 3k^2 - 3k + 1 \] This represents the difference of cubes. We can sum this from \(k=1\) to \(n\): \[ \Sigma_{k=1}^{n} (k^3 - (k-1)^3) = n^3 \] This is a well-known result in mathematics. **Hint for Step 5**: Review the properties of summation and cubes to understand why this identity holds. ### Conclusion - **Statement 1** is false as the calculated sum does not equal 8000. - **Statement 2** is true as it correctly states the summation of the difference of cubes. ### Final Answer - Statement 1: False - Statement 2: True

To solve the problem, we need to analyze the two statements provided: **Statement 1**: The sum of the series \(1 + (1 + 2 + 4) + (4 + 6 + 9) + (9 + 12 + 16) + \ldots + (361 + 380 + 400)\) is 8000. **Statement 2**: \(\Sigma_{k=1}^{n} (k^3 - (k-1)^3) = n^3\) for any natural number \(n\). ### Step-by-Step Solution ...
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