Partial Fractions: Integrate (4x+10)/(9x^2+24x+16)

arl146
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Homework Statement


determine the indefinite integral: ∫ (4x+10)/(9x^2+24x+16) dx


Homework Equations


partial fractions technique


The Attempt at a Solution



i know it's partial fractions and i thought i did it right but i got the wrong answer.

(4x+10)/(9x^2+24x+16) = (4x+10)/(3x+4)^2 = A/(3x+4) + B/(3x+4)^2
is that part right before I continue?
 
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arl146 said:

Homework Statement


determine the indefinite integral: ∫ (4x+10)/(9x^2+24x+16) dx


Homework Equations


partial fractions technique


The Attempt at a Solution



i know it's partial fractions and i thought i did it right but i got the wrong answer.

(4x+10)/(9x^2+24x+16) = (4x+10)/(3x+4)^2 = A/(3x+4) + B/(3x+4)^2
is that part right before I continue?

Yes, that is the right idea.

RGV
 
Yes, that's right.
 
arl146 said:

Homework Statement


determine the indefinite integral: ∫ (4x+10)/(9x^2+24x+16) dx


Homework Equations


partial fractions technique


The Attempt at a Solution



i know it's partial fractions and i thought i did it right but i got the wrong answer.

(4x+10)/(9x^2+24x+16) = (4x+10)/(3x+4)^2 = A/(3x+4) + B/(3x+4)^2
is that part right before I continue?
As others have told you that is correct. Now multiply both sides by (3x+4)^2 to get (4x+10)(3x+ 4)^2= A(3x+ 4)+ B. Taking x= -4/3 gives an easy solution for B. Take x to be any other number, say, x= 0, to get an equation for A.
 
ohhhh .. i see what i did. ok .. so i was doing A(3x+ 4)^2 + B(3x+4) not realizing the denominator difference. stupid mistake. thanks!
 
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