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If 2 + isqrt3 is a root of x^(3) - 6x^(2...

If `2 + isqrt3` is a root of `x^(3) - 6x^(2) + px + q = 0` (where `p` and `q` are real) then `p + q` is

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To solve the problem, we need to find the values of \( p \) and \( q \) given that \( 2 + i\sqrt{3} \) is a root of the polynomial equation \( x^3 - 6x^2 + px + q = 0 \). Since the coefficients \( p \) and \( q \) are real, the complex conjugate \( 2 - i\sqrt{3} \) must also be a root. ### Step 1: Find the third root Let the third root be \( r \). By Vieta's formulas, the sum of the roots is equal to the coefficient of \( x^2 \) with the opposite sign: \[ (2 + i\sqrt{3}) + (2 - i\sqrt{3}) + r = 6 \] Simplifying this, we have: \[ 4 + r = 6 \implies r = 2 \] ### Step 2: Write the polynomial The roots of the polynomial are \( 2 + i\sqrt{3} \), \( 2 - i\sqrt{3} \), and \( 2 \). The polynomial can be expressed as: \[ (x - (2 + i\sqrt{3}))(x - (2 - i\sqrt{3}))(x - 2) \] ### Step 3: Simplify the first two factors The product of the first two factors is: \[ (x - (2 + i\sqrt{3}))(x - (2 - i\sqrt{3})) = (x - 2)^2 + 3 \] This simplifies to: \[ (x - 2)^2 + 3 = (x^2 - 4x + 4 + 3) = x^2 - 4x + 7 \] ### Step 4: Multiply by the third factor Now we multiply this result by the third factor: \[ (x^2 - 4x + 7)(x - 2) \] Expanding this: \[ = x^3 - 2x^2 - 4x^2 + 8x + 7x - 14 \] Combining like terms: \[ = x^3 - 6x^2 + 15x - 14 \] ### Step 5: Identify \( p \) and \( q \) From the expanded polynomial \( x^3 - 6x^2 + 15x - 14 \), we can identify: \[ p = 15 \quad \text{and} \quad q = -14 \] ### Step 6: Calculate \( p + q \) Now we find \( p + q \): \[ p + q = 15 + (-14) = 1 \] ### Final Answer Thus, the value of \( p + q \) is: \[ \boxed{1} \]

To solve the problem, we need to find the values of \( p \) and \( q \) given that \( 2 + i\sqrt{3} \) is a root of the polynomial equation \( x^3 - 6x^2 + px + q = 0 \). Since the coefficients \( p \) and \( q \) are real, the complex conjugate \( 2 - i\sqrt{3} \) must also be a root. ### Step 1: Find the third root Let the third root be \( r \). By Vieta's formulas, the sum of the roots is equal to the coefficient of \( x^2 \) with the opposite sign: \[ (2 + i\sqrt{3}) + (2 - i\sqrt{3}) + r = 6 \] Simplifying this, we have: ...
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