Factor Denominator: Factor the denominator of the integrand.The denominator x2+x−6 can be factored into (x+3)(x−2).So, the integral becomes ∫(x+3)(x−2)9x+2dx.
Partial Fraction Decomposition: Perform partial fraction decomposition.We want to express (9x+2)/((x+3)(x−2)) as A/(x+3)+B/(x−2).To find A and B, we set up the equation 9x+2=A(x−2)+B(x+3).
Solve for A and B: Solve for A and B.To find A and B, we can use the method of equating coefficients or plugging in convenient values for x. Let's use the latter method.For x=2, we get 9(2)+2=B(2+3), which gives us B=(18+2)/5=4.For x=−3, we get 9(−3)+2=A(−3−2), which gives us A=(−27+2)/−5=5.
Rewrite with Partial Fractions: Rewrite the integral using the partial fractions.Now that we have A=5 and B=4, the integral becomes ∫(x+3)5dx+∫(x−2)4dx.
Integrate Each Term: Integrate each term separately.The integral of x+35dx is 5⋅ln∣x+3∣, and the integral of x−24dx is $\(4\) \cdot \ln|x - \(2\)|.
Combine and Add Constant: Combine the results and add the constant of integration. The final answer is \(5 \cdot \ln|x + 3| + 4 \cdot \ln|x - 2| + C\), where \(C\) is the constant of integration.
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