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If (5x^(2)+8x-2)/((3x-2)(x^(2)-x+3)) =(A...

If `(5x^(2)+8x-2)/((3x-2)(x^(2)-x+3)) =(A)/(3x-2)+(Bx+C)/(x^(2)-x+3)`, then `A+B+C=`………..

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To solve the equation \[ \frac{5x^2 + 8x - 2}{(3x - 2)(x^2 - x + 3)} = \frac{A}{3x - 2} + \frac{Bx + C}{x^2 - x + 3}, \] we will first combine the right-hand side into a single fraction. ### Step 1: Combine the Right-Hand Side The common denominator for the right-hand side is \((3x - 2)(x^2 - x + 3)\). Thus, we can write: \[ \frac{A}{3x - 2} + \frac{Bx + C}{x^2 - x + 3} = \frac{A(x^2 - x + 3) + (Bx + C)(3x - 2)}{(3x - 2)(x^2 - x + 3)}. \] ### Step 2: Expand the Numerator Now we will expand the numerator: \[ A(x^2 - x + 3) + (Bx + C)(3x - 2). \] Expanding \(A(x^2 - x + 3)\): \[ Ax^2 - Ax + 3A. \] Expanding \((Bx + C)(3x - 2)\): \[ 3Bx^2 - 2Bx + 3Cx - 2C = 3Bx^2 + (3C - 2B)x - 2C. \] Combining these, we have: \[ (A + 3B)x^2 + (-A + 3C - 2B)x + (3A - 2C). \] ### Step 3: Set the Numerator Equal to the Left-Hand Side Now we equate this to the left-hand side: \[ 5x^2 + 8x - 2 = (A + 3B)x^2 + (-A + 3C - 2B)x + (3A - 2C). \] ### Step 4: Compare Coefficients Now we can compare the coefficients of \(x^2\), \(x\), and the constant term: 1. For \(x^2\): \[ A + 3B = 5 \quad \text{(1)} \] 2. For \(x\): \[ -A + 3C - 2B = 8 \quad \text{(2)} \] 3. For the constant term: \[ 3A - 2C = -2 \quad \text{(3)} \] ### Step 5: Solve the System of Equations From equation (1), we can express \(A\) in terms of \(B\): \[ A = 5 - 3B \quad \text{(4)} \] Substituting (4) into equation (2): \[ -(5 - 3B) + 3C - 2B = 8, \] which simplifies to: \[ -5 + 3B + 3C - 2B = 8 \implies B + 3C = 13 \quad \text{(5)}. \] Now substituting (4) into equation (3): \[ 3(5 - 3B) - 2C = -2, \] which simplifies to: \[ 15 - 9B - 2C = -2 \implies -9B - 2C = -17 \implies 9B + 2C = 17 \quad \text{(6)}. \] ### Step 6: Solve Equations (5) and (6) Now we have a system of two equations: 1. \(B + 3C = 13\) (5) 2. \(9B + 2C = 17\) (6) From equation (5), we can express \(C\) in terms of \(B\): \[ C = \frac{13 - B}{3} \quad \text{(7)}. \] Substituting (7) into equation (6): \[ 9B + 2\left(\frac{13 - B}{3}\right) = 17. \] Multiplying through by 3 to eliminate the fraction: \[ 27B + 2(13 - B) = 51 \implies 27B + 26 - 2B = 51 \implies 25B = 25 \implies B = 1. \] ### Step 7: Find \(A\) and \(C\) Substituting \(B = 1\) back into equation (4): \[ A = 5 - 3(1) = 2. \] Substituting \(B = 1\) into equation (7): \[ C = \frac{13 - 1}{3} = \frac{12}{3} = 4. \] ### Step 8: Calculate \(A + B + C\) Now we can find \(A + B + C\): \[ A + B + C = 2 + 1 + 4 = 7. \] Thus, the final answer is: \[ \boxed{7}. \]
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