Multiply by Denominator: We want to express (9x−5)/(2(2x−1)(x−1)) as A/(2x−1)+B/(x−1). To find A and B, we'll multiply both sides by the denominator 2(2x−1)(x−1).
Equation with A and B: So we have 9x−5=A(2x−1)(x−1)+B(2(2x−1)). Now we'll find the values of A and B by choosing suitable values for x.
Plug in x=1: Let's plug in x=1 to get rid of the A term. We get 9(1)−5=B(2(2(1)−1)), which simplifies to 4=2B, so B=2.
Plug in x=21: Now let's plug in x=21 to get rid of the B term. We get 9(21)−5=A(2(21)−1)((21)−1), which simplifies to −4.5=A(0)((−21)), so A=0.
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