SOLUTION: . Solve the following into partial fractions x 3 + 4 x 2 + 20 x - 7 ----------- ----------- - ( x - 1) 2 ( x2 + 8)

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Question 1038903: . Solve the following into partial fractions
x 3 + 4 x 2 + 20 x - 7
-------------------------
( x - 1) 2 ( x2 + 8)
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!




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x%5E3 terms,
1=a%2Bc
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x%5E2 terms,
4=-a%2Bb-2c%2Bd
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x terms,
20=8a%2Bc-2d
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constant term,
-7=-8a%2B8b%2Bd
Using Cramer's rule,

abs%28A%29=81
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abs%28A%5Ba%5D%29=243
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abs%28A%5Bb%5D%29=162
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abs%28A%5Bc%5D%29=-162
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abs%28A%5Bd%5D%29=81
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So,
a=abs%28A%5Ba%5D%29%2Fabs%28A%29=243%2F81=3
b=abs%28A%5Bb%5D%29%2Fabs%28A%29=162%2F81=2
c=abs%28A%5Bc%5D%29%2Fabs%28A%29-162%2F81=-2
d=abs%28A%5Bd%5D%29%2Fabs%28A%29=81%2F81=1
So,