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If int(x^(2)-x^(3))/(x^(3)-2x^(2)-x+2)...

If
`int(x^(2)-x^(3))/(x^(3)-2x^(2)-x+2)dx=Alog(c|((x+1))/(x-2)^(4)|)` then A is equal to.

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The correct Answer is:
To solve the integral \[ \int \frac{x^2 - x^3}{x^3 - 2x^2 - x + 2} \, dx, \] we start by simplifying the integrand. ### Step 1: Factor the Denominator First, we need to factor the denominator \(x^3 - 2x^2 - x + 2\). We can check for rational roots using the Rational Root Theorem. Testing \(x = 1\): \[ 1^3 - 2(1^2) - 1 + 2 = 1 - 2 - 1 + 2 = 0. \] So, \(x - 1\) is a factor. We can perform polynomial long division or synthetic division to factor the cubic polynomial. After performing synthetic division of \(x^3 - 2x^2 - x + 2\) by \(x - 1\), we get: \[ x^3 - 2x^2 - x + 2 = (x - 1)(x^2 - x - 2). \] Next, we factor \(x^2 - x - 2\): \[ x^2 - x - 2 = (x - 2)(x + 1). \] Thus, the complete factorization of the denominator is: \[ x^3 - 2x^2 - x + 2 = (x - 1)(x - 2)(x + 1). \] ### Step 2: Rewrite the Integral Now we can rewrite the integral: \[ \int \frac{x^2 - x^3}{(x - 1)(x - 2)(x + 1)} \, dx. \] ### Step 3: Simplify the Numerator We can factor out \(x^2\) from the numerator: \[ x^2 - x^3 = -x^3 + x^2 = -x^2(x - 1). \] Thus, we have: \[ \int \frac{-x^2(x - 1)}{(x - 1)(x - 2)(x + 1)} \, dx = \int \frac{-x^2}{(x - 2)(x + 1)} \, dx. \] ### Step 4: Use Partial Fraction Decomposition Next, we perform partial fraction decomposition on \(\frac{-x^2}{(x - 2)(x + 1)}\): \[ \frac{-x^2}{(x - 2)(x + 1)} = \frac{A}{x - 2} + \frac{B}{x + 1}. \] Multiplying through by the denominator \((x - 2)(x + 1)\) gives: \[ -x^2 = A(x + 1) + B(x - 2). \] Expanding and collecting like terms, we can solve for \(A\) and \(B\) by substituting convenient values for \(x\). ### Step 5: Solve for Constants Substituting \(x = 2\): \[ -4 = A(3) + B(0) \implies A = -\frac{4}{3}. \] Substituting \(x = -1\): \[ -1 = A(0) + B(-3) \implies B = \frac{1}{3}. \] ### Step 6: Rewrite the Integral Now we can rewrite the integral: \[ \int \left(-\frac{4}{3(x - 2)} + \frac{1}{3(x + 1)}\right) \, dx. \] ### Step 7: Integrate Integrating term by term gives: \[ -\frac{4}{3} \ln |x - 2| + \frac{1}{3} \ln |x + 1| + C. \] ### Step 8: Combine Logarithms Combining the logarithms: \[ \frac{1}{3} \ln \left| \frac{(x + 1)}{(x - 2)^{4}} \right| + C. \] ### Step 9: Compare with Given Form Given that: \[ \int \frac{x^2 - x^3}{x^3 - 2x^2 - x + 2} \, dx = A \ln \left| \frac{(x + 1)}{(x - 2)^{4}} \right|, \] we can see that \(A = \frac{1}{3}\). ### Final Answer Thus, the value of \(A\) is: \[ \boxed{\frac{1}{3}}. \]
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