I can't seem to do this with partial fractions

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skyturnred
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Homework Statement



[itex]\frac{x}{(x+4)^{2}}[/itex]

Homework Equations





The Attempt at a Solution



I make the integrand equal to the following:

[itex]\frac{A}{(x+4)}[/itex]+[itex]\frac{Bx+C}{(x+4)^{2}}[/itex]

Then after finding a common denominator I get

x = A(x+4)[itex]^{2}[/itex]+(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



[itex]\frac{x}{(x+4)^{2}}[/itex]

Homework Equations





The Attempt at a Solution



I make the integrand equal to the following:

[itex]\frac{A}{(x+4)}[/itex]+[itex]\frac{Bx+C}{(x+4)^{2}}[/itex]

Then after finding a common denominator I get

x = A(x+4)[itex]^{2}[/itex]+(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:

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

Multiplying by (x+4)2 gives:

[itex]\displaystyle x=A(x+4)+Bx+C[/itex]