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If f(x)=a=b x+c x^2a n dalpha,beta,gamma...

If `f(x)=a=b x+c x^2a n dalpha,beta,gamma` are the roots of the equation `x^3=1,t h e n|a b c b c a c a b|` is equal to `f(alpha)+f(beta)+f(gamma)` `f(alpha)f(beta)+f(beta)f(gamma)+f(gamma)f(alpha)` `f(alpha)f(beta)f(gamma)` `-f(alpha)f(beta)f(gamma)`

A

`f(alpha) +f(beta) +f(gamma)`

B

`f(alpha) f(beta)+f(beta)f(gamma)+f(gamma) f(alpha)`

C

`f(alpha) f(beta) f(gamma)`

D

`-f(alpha) f(beta)f(gamma)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to analyze the function \( f(x) = ax + bx + cx^2 \) and the roots of the equation \( x^3 = 1 \), which are \( \alpha, \beta, \gamma \). The roots of this equation are the cube roots of unity: \( \omega, \omega^2, 1 \), where \( \omega = e^{2\pi i / 3} \). ### Step-by-Step Solution: 1. **Identify the Roots**: The roots of the equation \( x^3 = 1 \) are: \[ \alpha = 1, \quad \beta = \omega, \quad \gamma = \omega^2 \] 2. **Evaluate \( f(\alpha), f(\beta), f(\gamma) \)**: We need to evaluate \( f \) at each of the roots: - For \( \alpha = 1 \): \[ f(1) = a(1) + b(1) + c(1^2) = a + b + c \] - For \( \beta = \omega \): \[ f(\omega) = a(\omega) + b(\omega) + c(\omega^2) = a\omega + b\omega + c\omega^2 \] - For \( \gamma = \omega^2 \): \[ f(\omega^2) = a(\omega^2) + b(\omega^2) + c(\omega) = a\omega^2 + b\omega^2 + c\omega \] 3. **Use the Properties of Roots of Unity**: The sum of the roots \( \alpha + \beta + \gamma = 1 + \omega + \omega^2 = 0 \). This property will help simplify our calculations. 4. **Calculate the Determinant**: We need to calculate the determinant: \[ |a \quad b \quad c| \] \[ |b \quad c \quad a| \] \[ |c \quad a \quad b| \] Using the determinant properties, we can simplify this to: \[ = abc - (a^3 + b^3 + c^3 - 3abc) \] This can be factored as: \[ = - (a + b + c)(a + b\omega + c\omega^2)(a + b\omega^2 + c\omega) \] 5. **Final Result**: The determinant can be expressed in terms of \( f(\alpha), f(\beta), f(\gamma) \): \[ = -f(\alpha)f(\beta)f(\gamma) \] Therefore, the correct option is: \[ -f(\alpha)f(\beta)f(\gamma) \] ### Conclusion: The answer to the problem is: \[ \text{The value of the determinant is } -f(\alpha)f(\beta)f(\gamma). \]

To solve the given problem, we need to analyze the function \( f(x) = ax + bx + cx^2 \) and the roots of the equation \( x^3 = 1 \), which are \( \alpha, \beta, \gamma \). The roots of this equation are the cube roots of unity: \( \omega, \omega^2, 1 \), where \( \omega = e^{2\pi i / 3} \). ### Step-by-Step Solution: 1. **Identify the Roots**: The roots of the equation \( x^3 = 1 \) are: \[ \alpha = 1, \quad \beta = \omega, \quad \gamma = \omega^2 ...
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