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If : int(2x^(2)+3)/((x^(2)-1)(x^(2)-4))d...

If : `int(2x^(2)+3)/((x^(2)-1)(x^(2)-4))dx=log[((x-2)/(x+))^(a).((x+1)/(x-1))^(b)]+c` then : `(a, b)-=`

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To solve the integral \[ \int \frac{2x^2 + 3}{(x^2 - 1)(x^2 - 4)} \, dx, \] we will use partial fraction decomposition. ### Step 1: Set up the partial fraction decomposition We can express the integrand as: \[ \frac{2x^2 + 3}{(x^2 - 1)(x^2 - 4)} = \frac{A}{x^2 - 1} + \frac{B}{x^2 - 4}. \] ### Step 2: Multiply through by the denominator Multiplying both sides by \((x^2 - 1)(x^2 - 4)\) gives: \[ 2x^2 + 3 = A(x^2 - 4) + B(x^2 - 1). \] ### Step 3: Expand the right-hand side Expanding the right-hand side: \[ 2x^2 + 3 = Ax^2 - 4A + Bx^2 - B = (A + B)x^2 + (-4A - B). \] ### Step 4: Set up equations for coefficients Now, we can equate the coefficients: 1. For \(x^2\): \(A + B = 2\) 2. For the constant term: \(-4A - B = 3\) ### Step 5: Solve the system of equations From the first equation, we can express \(B\) in terms of \(A\): \[ B = 2 - A. \] Substituting this into the second equation: \[ -4A - (2 - A) = 3 \implies -4A - 2 + A = 3 \implies -3A = 5 \implies A = -\frac{5}{3}. \] Now substituting \(A\) back to find \(B\): \[ B = 2 - \left(-\frac{5}{3}\right) = 2 + \frac{5}{3} = \frac{6}{3} + \frac{5}{3} = \frac{11}{3}. \] ### Step 6: Rewrite the integral Now we can rewrite the integral: \[ \int \left( \frac{-\frac{5}{3}}{x^2 - 1} + \frac{\frac{11}{3}}{x^2 - 4} \right) dx. \] ### Step 7: Integrate each term Now we can integrate each term separately: 1. For \(\int \frac{-\frac{5}{3}}{x^2 - 1} \, dx\): \[ = -\frac{5}{3} \cdot \frac{1}{2} \log \left| \frac{x - 1}{x + 1} \right| = -\frac{5}{6} \log \left| \frac{x - 1}{x + 1} \right|. \] 2. For \(\int \frac{\frac{11}{3}}{x^2 - 4} \, dx\): \[ = \frac{11}{3} \cdot \frac{1}{2} \log \left| \frac{x - 2}{x + 2} \right| = \frac{11}{6} \log \left| \frac{x - 2}{x + 2} \right|. \] ### Step 8: Combine results Combining these results, we have: \[ -\frac{5}{6} \log \left| \frac{x - 1}{x + 1} \right| + \frac{11}{6} \log \left| \frac{x - 2}{x + 2} \right| + C. \] ### Step 9: Rewrite in the required form Using properties of logarithms, we can combine these logarithms: \[ = \log \left( \left( \frac{x - 2}{x + 2} \right)^{\frac{11}{6}} \cdot \left( \frac{x + 1}{x - 1} \right)^{-\frac{5}{6}} \right) + C. \] ### Step 10: Identify values of \(a\) and \(b\) From the expression, we can identify: - \(a = \frac{11}{6}\) - \(b = -\frac{5}{6}\) Thus, the final answer is: \[ (a, b) = \left(\frac{11}{6}, -\frac{5}{6}\right). \]
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