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For which values of a and b are zeroes of q(X)`=x^(3)+2x+a` also zeroes of the polynomial p(x)`=x^(5)-x^(4)-4x^(3)+3x^(2)+3x+b`? Which zeroes of p(x) are not zeroes of p(x)?

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To solve the problem, we need to find the values of \( a \) and \( b \) such that the zeros of the polynomial \( q(x) = x^3 + 2x^2 + a \) are also zeros of the polynomial \( p(x) = x^5 - x^4 - 4x^3 + 3x^2 + 3x + b \). ### Step 1: Understand the problem We need to determine the values of \( a \) and \( b \) such that every root (zero) of \( q(x) \) is also a root of \( p(x) \). This means that \( q(x) \) must be a factor of \( p(x) \). ### Step 2: Perform polynomial long division To check if \( q(x) \) is a factor of \( p(x) \), we can use polynomial long division. We will divide \( p(x) \) by \( q(x) \). 1. **Divide the leading term**: The leading term of \( p(x) \) is \( x^5 \) and the leading term of \( q(x) \) is \( x^3 \). We divide \( x^5 \) by \( x^3 \) to get \( x^2 \). 2. **Multiply \( q(x) \) by \( x^2 \)**: \[ x^2 \cdot (x^3 + 2x^2 + a) = x^5 + 2x^4 + ax^2 \] 3. **Subtract from \( p(x) \)**: \[ p(x) - (x^5 + 2x^4 + ax^2) = (-1 - 2)x^4 + (-4 - a)x^3 + 3x^2 + 3x + b \] This simplifies to: \[ -3x^4 + (-4 - a)x^3 + 3x^2 + 3x + b \] ### Step 3: Continue the division 4. **Divide the leading term again**: The leading term is now \( -3x^4 \). Divide by \( x^3 \) to get \( -3x \). 5. **Multiply \( q(x) \) by \( -3x \)**: \[ -3x(x^3 + 2x^2 + a) = -3x^4 - 6x^3 - 3ax \] 6. **Subtract again**: \[ (-4 - a + 6)x^3 + (3 + 3a)x + b \] This simplifies to: \[ (2 - a)x^3 + (3 + 3a)x + b \] ### Step 4: Final division step 7. **Divide the leading term**: The leading term is \( (2 - a)x^3 \). Divide by \( x^3 \) to get \( 2 - a \). 8. **Multiply \( q(x) \) by \( (2 - a) \)**: \[ (2 - a)(x^3 + 2x^2 + a) = (2 - a)x^3 + 2(2 - a)x^2 + (2 - a)a \] 9. **Subtract**: \[ (3 + 3a - 2(2 - a))x^2 + (b - (2 - a)a) \] This gives: \[ (3 + 3a - 4 + 2a)x^2 + (b - (2a - a^2)) \] Simplifying gives: \[ (5a - 1)x^2 + (b - 2a + a^2) \] ### Step 5: Set the remainder to zero For \( q(x) \) to be a factor of \( p(x) \), the remainder must be zero: 1. Set \( 5a - 1 = 0 \) → \( a = \frac{1}{5} \) 2. Set \( b - 2a + a^2 = 0 \): \[ b = 2a - a^2 \] Substituting \( a = \frac{1}{5} \): \[ b = 2 \cdot \frac{1}{5} - \left(\frac{1}{5}\right)^2 = \frac{2}{5} - \frac{1}{25} = \frac{10}{25} - \frac{1}{25} = \frac{9}{25} \] ### Final values Thus, the values of \( a \) and \( b \) are: \[ a = \frac{1}{5}, \quad b = \frac{9}{25} \] ### Step 6: Identify zeros of \( p(x) \) that are not zeros of \( q(x) \) To find the zeros of \( p(x) \) and \( q(x) \): - The zeros of \( q(x) \) are the solutions to \( x^3 + 2x^2 + \frac{1}{5} = 0 \). - The zeros of \( p(x) \) are the solutions to \( x^5 - x^4 - 4x^3 + 3x^2 + 3x + \frac{9}{25} = 0 \). After solving both equations, we can identify which zeros of \( p(x) \) are not zeros of \( q(x) \).

To solve the problem, we need to find the values of \( a \) and \( b \) such that the zeros of the polynomial \( q(x) = x^3 + 2x^2 + a \) are also zeros of the polynomial \( p(x) = x^5 - x^4 - 4x^3 + 3x^2 + 3x + b \). ### Step 1: Understand the problem We need to determine the values of \( a \) and \( b \) such that every root (zero) of \( q(x) \) is also a root of \( p(x) \). This means that \( q(x) \) must be a factor of \( p(x) \). ### Step 2: Perform polynomial long division To check if \( q(x) \) is a factor of \( p(x) \), we can use polynomial long division. We will divide \( p(x) \) by \( q(x) \). ...
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