Factor Denominator: Factor the denominator of the integrand.The denominator x2−4x+3 can be factored into (x−1)(x−3).
Perform Division: Perform polynomial long division or synthetic division to divide the numerator by the denominator.We divide x3−4x2+5x−2 by x2−4x+3.
Quotient and Remainder: After performing the division, we get a quotient and a remainder. The quotient is x−1 and the remainder is 2x−5. So, the integral becomes ∫(x−1)dx+∫x2−4x+32x−5dx.
Integrate First Part: Integrate the first part of the integral, which is ∫(x−1)dx. The integral of x with respect to x is (1/2)x2 and the integral of −1 with respect to x is −x. So, ∫(x−1)dx=(1/2)x2−x.
Decompose Fraction: Decompose the fractions" target="_blank" class="backlink">fraction (2x−5)/(x2−4x+3) into partial fractions.We write (2x−5)/(x2−4x+3) as A/(x−1)+B/(x−3).
Solve for A and B: Solve for A and B by multiplying both sides by the denominator x2−4x+3 and comparing coefficients.We get 2x−5=A(x−3)+B(x−1).
Plug in Values: Plug in values for x to solve for A and B. Let x=1, then 2(1)−5=A(1−3), which gives A=23. Let x=3, then 2(3)−5=B(3−1), which gives B=21.
Rewrite with Partial Fractions: Rewrite the integral with the found partial fractions.The integral becomes ∫(x−1)dx + ∫23÷(x−1)dx + ∫21÷(x−3)dx.
Integrate Partial Fractions: Integrate the partial fractions.The integral of (23)/(x−1) with respect to x is (23)ln∣x−1∣, and the integral of (21)/(x−3) with respect to x is (21)ln∣x−3∣.
Combine Integrated Parts: Combine all the integrated parts to get the final answer.The final integral is (21)x2−x+(23)ln∣x−1∣+(21)ln∣x−3∣+C, where C is the constant of integration.
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