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3 votes
9x-20/(x+6)^2 partial fraction decomposition

User Flownt
by
4.6k points

2 Answers

4 votes

Answer:

Find the partial fraction decomposition of 6x+8/x2-9x+8

Explanation:

User Tevya
by
5.7k points
1 vote

We're looking for
a,b such that


(9x-20)/((x+6)^2)=\frac a{x+6}+\frac b{(x+6)^2}

Multiplying both sides by
(x+6)^2 gives us


9x-20=a(x+6)+b

Notice that when
x=-6, the term involving
a vanishes and we're left with


9(-6)-20=b\implies b=-74

Then


9x-20=a(x+6)-74=ax+6a-74\implies a=9

so that


(9x-20)/((x+6)^2)=\boxed{\frac9{x+6}-(74)/((x+6)^2)}

User Kusalananda
by
5.8k points
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