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If (x + 2) and (x + 3) are factors of `x^(3)+ax+b`, find the value of 'a' and 'b'.

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To solve the problem, we need to find the values of 'a' and 'b' given that \( (x + 2) \) and \( (x + 3) \) are factors of the polynomial \( x^3 + ax + b \). ### Step 1: Set up the equations using the factors Since \( (x + 2) \) and \( (x + 3) \) are factors, we know that if we substitute \( x = -2 \) and \( x = -3 \) into the polynomial, the result should be zero. ### Step 2: Substitute \( x = -2 \) Substituting \( x = -2 \) into the polynomial: \[ (-2)^3 + a(-2) + b = 0 \] This simplifies to: \[ -8 - 2a + b = 0 \] Rearranging gives us: \[ -2a + b = 8 \quad \text{(Equation 1)} \] ### Step 3: Substitute \( x = -3 \) Now, substituting \( x = -3 \) into the polynomial: \[ (-3)^3 + a(-3) + b = 0 \] This simplifies to: \[ -27 - 3a + b = 0 \] Rearranging gives us: \[ -3a + b = 27 \quad \text{(Equation 2)} \] ### Step 4: Solve the system of equations Now we have a system of two equations: 1. \( -2a + b = 8 \) 2. \( -3a + b = 27 \) We can eliminate \( b \) by subtracting Equation 1 from Equation 2: \[ (-3a + b) - (-2a + b) = 27 - 8 \] This simplifies to: \[ -a = 19 \] Thus, we find: \[ a = -19 \] ### Step 5: Substitute back to find \( b \) Now, substitute \( a = -19 \) back into Equation 1 to find \( b \): \[ -2(-19) + b = 8 \] This simplifies to: \[ 38 + b = 8 \] Rearranging gives: \[ b = 8 - 38 = -30 \] ### Conclusion The values of \( a \) and \( b \) are: \[ a = -19, \quad b = -30 \]
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