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

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`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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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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MCGROW HILL PUBLICATION-INDEFINITE INTEGRATION-SOLVED EXAMPLE ( NUMERICAL ANSWER TYPE QUESTION )
  1. If int(x^(2)-x^(3))/(x^(3)-2x^(2)-x+2)dx=Alog(c|((x+1))/(x-2)^(4)|) ...

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  2. If int(x^(2)-1)/((x^(2)+1)sqrt(x^(4)+1))dx is equal to Atan^(-1)((1)/(...

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  3. If the graph of the antiderivative F(x) of f(x) = log(log x) + (log x)...

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  4. If int(cos^(2)x+sin2x)/((2cosx-sinx))dx=(-A)/(25)x-(2)/(5)log|2cosx-si...

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  5. If int(2e^(5x)+e^(4x)-4e^(3x)+2e^(x))/((e^(2x)+4)(e^(2x)-1)^(2))dx=tan...

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  6. If int(x^(3))/(4+x^(16))dx=(A)/(8)tan^(-1)(z)/(sqrt(2))-(1)/(64)log |(...

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  7. If int(cos^(2)xsinx)/(sinx-cosx)dx=A log|sinx-cosx|+(1)/(8)(sin2x+cos2...

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  8. If I = int(sinx(cosx)^(-5//2)dx)/(sqrt(sinx+3cosx)+sqrt(sinx+4cosx)) ...

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  9. If int(cos^(3)xdz)/((sin^(4)+x+3sin^(2)x+1)tan^(-1)(sinx+cosec x))=-...

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  10. I=(xcosx+1)/(sqrt(2x^(3)e^(sinx)+x^(2)))dx (4)/(5)Alog|sqrt(2xe^(sin...

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  11. I=int(dx)/(2xsqrt(1-x)sqrt(2-x+sqrt(1-x)))=-(1)/(2sqrt(3))log|u+(1)/(2...

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  12. If I = int(dx)/(1+sqrt(x^(2)+2x+2))=(5)/(8)Alog|x+1+sqrt(x^(2)+2x+2)|-...

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  13. If intsqrt(1+3sqrt(x))/(3sqrt(x^(2)))dx=2f(x)+C, then f(27) is equal t...

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  14. If I = int(sqrt(cot)x-sqrt(tan)x)/(1+3sin2x)dx=Atan^(-1)((sqrt(tan)x+s...

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  15. If . int(cos^(2)xsinx)/(sinx-cosx)dx=Alog|sinx-cosx|+(1)/(8)(sin2x+cos...

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  16. If I=int(cos^(3)xdx)/((sin^(4)x+3sin^(2)x+1)tan^(-1)(sinx+cosecx)) =...

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