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Satement 1 If the nth termn of a series ...

Satement 1 If the nth termn of a series is `2n^(3)+3n^(2)-4`, then the second order differences must be an AP.
Statement 2 If nth term of a series is a polynomial of degree m, then mth order differences of series are constant.

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, Statement 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

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The correct Answer is:
To solve the problem, we need to analyze the two statements given: **Statement 1:** If the nth term of a series is \(2n^3 + 3n^2 - 4\), then the second order differences must be an AP (Arithmetic Progression). **Statement 2:** If the nth term of a series is a polynomial of degree \(m\), then the \(m\)th order differences of the series are constant. ### Step-by-Step Solution: 1. **Identify the nth term:** The nth term of the series is given as: \[ T(n) = 2n^3 + 3n^2 - 4 \] 2. **Calculate the first few terms of the series:** We will calculate the first five terms by substituting \(n = 1, 2, 3, 4, 5\): - For \(n = 1\): \[ T(1) = 2(1)^3 + 3(1)^2 - 4 = 2 + 3 - 4 = 1 \] - For \(n = 2\): \[ T(2) = 2(2)^3 + 3(2)^2 - 4 = 2(8) + 3(4) - 4 = 16 + 12 - 4 = 24 \] - For \(n = 3\): \[ T(3) = 2(3)^3 + 3(3)^2 - 4 = 2(27) + 3(9) - 4 = 54 + 27 - 4 = 77 \] - For \(n = 4\): \[ T(4) = 2(4)^3 + 3(4)^2 - 4 = 2(64) + 3(16) - 4 = 128 + 48 - 4 = 172 \] - For \(n = 5\): \[ T(5) = 2(5)^3 + 3(5)^2 - 4 = 2(125) + 3(25) - 4 = 250 + 75 - 4 = 321 \] The first five terms are: \[ T(1) = 1, \quad T(2) = 24, \quad T(3) = 77, \quad T(4) = 172, \quad T(5) = 321 \] 3. **Calculate the first order differences:** The first order differences are calculated as follows: \[ D_1(1) = T(2) - T(1) = 24 - 1 = 23 \] \[ D_1(2) = T(3) - T(2) = 77 - 24 = 53 \] \[ D_1(3) = T(4) - T(3) = 172 - 77 = 95 \] \[ D_1(4) = T(5) - T(4) = 321 - 172 = 149 \] The first order differences are: \[ D_1 = 23, \quad 53, \quad 95, \quad 149 \] 4. **Calculate the second order differences:** The second order differences are calculated as follows: \[ D_2(1) = D_1(2) - D_1(1) = 53 - 23 = 30 \] \[ D_2(2) = D_1(3) - D_1(2) = 95 - 53 = 42 \] \[ D_2(3) = D_1(4) - D_1(3) = 149 - 95 = 54 \] The second order differences are: \[ D_2 = 30, \quad 42, \quad 54 \] 5. **Check if the second order differences are in AP:** To check if the second order differences are in AP, we calculate the differences between them: \[ D_2(2) - D_2(1) = 42 - 30 = 12 \] \[ D_2(3) - D_2(2) = 54 - 42 = 12 \] Since the differences are constant (both equal to 12), the second order differences are indeed in AP. ### Conclusion: - **Statement 1 is True**: The second order differences are in AP. - **Statement 2 is True**: The \(m\)th order differences of a polynomial of degree \(m\) are constant. Thus, both statements are true, and Statement 2 provides a correct explanation for Statement 1.

To solve the problem, we need to analyze the two statements given: **Statement 1:** If the nth term of a series is \(2n^3 + 3n^2 - 4\), then the second order differences must be an AP (Arithmetic Progression). **Statement 2:** If the nth term of a series is a polynomial of degree \(m\), then the \(m\)th order differences of the series are constant. ### Step-by-Step Solution: ...
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