I can't seem to do this with partial fractions

skyturnred
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Homework Statement



\frac{x}{(x+4)^{2}}

Homework Equations





The Attempt at a Solution



I make the integrand equal to the following:

\frac{A}{(x+4)}+\frac{Bx+C}{(x+4)^{2}}

Then after finding a common denominator I get

x = A(x+4)^{2}+(Bx+C)(x+4)

But that cannot be possible because when you set x=-4, you get -4=0. Any help please?

Also if you have ANY tips whatsoever about partial fractions please tell me them!
 
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skyturnred said:

Homework Statement



\frac{x}{(x+4)^{2}}

Homework Equations





The Attempt at a Solution



I make the integrand equal to the following:

\frac{A}{(x+4)}+\frac{Bx+C}{(x+4)^{2}}

Then after finding a common denominator I get

x = A(x+4)^{2}+(Bx+C)(x+4)

But that cannot be possible because when you set x=-4, you get -4=0. Any help please?

Also if you have ANY tips whatsoever about partial fractions please tell me them!
Algebra check:

\displaystyle\frac{x}{(x+4)^{2}}=\frac{A}{(x+4)}+ \frac{Bx+C}{(x+4)^{2}}

Multiplying by (x+4)2 gives:

\displaystyle x=A(x+4)+Bx+C
 
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