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Let f(x)=x^(3)+x+1, let p(x) be a cubic ...

Let `f(x)=x^(3)+x+1`, let `p(x)` be a cubic polynomial such that the roots of `p(x)=0` are the squares of the roots of `f(x)=0` , then

A

`p(1)=3`

B

the value of `P(n)`, `n in N` is odd

C

Sum of all roots of `p(x)=0` is `-2`

D

Sum of all product of roots taken two at a time is `1`

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To solve the problem, we need to find the polynomial \( p(x) \) whose roots are the squares of the roots of the polynomial \( f(x) = x^3 + x + 1 \). ### Step-by-step Solution: 1. **Identify the Roots of \( f(x) \)**: Let the roots of \( f(x) = 0 \) be \( \alpha_1, \alpha_2, \alpha_3 \). According to Vieta's formulas, we have: - Sum of roots: \( \alpha_1 + \alpha_2 + \alpha_3 = 0 \) - Sum of products of roots taken two at a time: \( \alpha_1\alpha_2 + \alpha_2\alpha_3 + \alpha_3\alpha_1 = 1 \) - Product of roots: \( \alpha_1\alpha_2\alpha_3 = -1 \) 2. **Roots of \( p(x) \)**: The roots of \( p(x) \) are \( \alpha_1^2, \alpha_2^2, \alpha_3^2 \). We need to find the polynomial whose roots are these squares. 3. **Sum of the Roots of \( p(x) \)**: The sum of the roots \( \alpha_1^2 + \alpha_2^2 + \alpha_3^2 \) can be calculated using the identity: \[ \alpha_1^2 + \alpha_2^2 + \alpha_3^2 = (\alpha_1 + \alpha_2 + \alpha_3)^2 - 2(\alpha_1\alpha_2 + \alpha_2\alpha_3 + \alpha_3\alpha_1) \] Substituting the values from Vieta's: \[ \alpha_1^2 + \alpha_2^2 + \alpha_3^2 = 0^2 - 2 \cdot 1 = -2 \] 4. **Sum of the Products of Roots Taken Two at a Time**: The sum of the products of the roots taken two at a time \( \alpha_1^2\alpha_2^2 + \alpha_2^2\alpha_3^2 + \alpha_3^2\alpha_1^2 \) can be calculated as: \[ \alpha_1^2\alpha_2^2 + \alpha_2^2\alpha_3^2 + \alpha_3^2\alpha_1^2 = (\alpha_1\alpha_2)^2 + (\alpha_2\alpha_3)^2 + (\alpha_3\alpha_1)^2 \] Using the identity: \[ (\alpha_1\alpha_2 + \alpha_2\alpha_3 + \alpha_3\alpha_1)^2 = (\alpha_1\alpha_2)^2 + (\alpha_2\alpha_3)^2 + (\alpha_3\alpha_1)^2 + 2\alpha_1\alpha_2\alpha_3(\alpha_1 + \alpha_2 + \alpha_3) \] Substituting the known values: \[ 1^2 = (\alpha_1\alpha_2)^2 + (\alpha_2\alpha_3)^2 + (\alpha_3\alpha_1)^2 + 2(-1)(0) \] Thus, \[ (\alpha_1\alpha_2)^2 + (\alpha_2\alpha_3)^2 + (\alpha_3\alpha_1)^2 = 1 \] 5. **Product of the Roots**: The product of the roots \( \alpha_1^2\alpha_2^2\alpha_3^2 \) is given by: \[ (\alpha_1\alpha_2\alpha_3)^2 = (-1)^2 = 1 \] 6. **Construct the Polynomial \( p(x) \)**: Using the results from the previous steps, we can construct the polynomial \( p(x) \) using Vieta's relations: \[ p(x) = x^3 - (\text{sum of roots})x^2 + (\text{sum of products of roots taken two at a time})x - (\text{product of roots}) \] Substituting the values: \[ p(x) = x^3 - (-2)x^2 + 1x - 1 = x^3 + 2x^2 + x - 1 \] ### Final Result: The polynomial \( p(x) \) is: \[ p(x) = x^3 + 2x^2 + x - 1 \]

To solve the problem, we need to find the polynomial \( p(x) \) whose roots are the squares of the roots of the polynomial \( f(x) = x^3 + x + 1 \). ### Step-by-step Solution: 1. **Identify the Roots of \( f(x) \)**: Let the roots of \( f(x) = 0 \) be \( \alpha_1, \alpha_2, \alpha_3 \). According to Vieta's formulas, we have: - Sum of roots: \( \alpha_1 + \alpha_2 + \alpha_3 = 0 \) - Sum of products of roots taken two at a time: \( \alpha_1\alpha_2 + \alpha_2\alpha_3 + \alpha_3\alpha_1 = 1 \) ...
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