Respuesta :

yee, partial fractions

remember some things to solve:

[tex]\frac{px+q}{(x+a)(x+b)}=\frac{A}{x+a}+\frac{B}{x+b}[/tex]

[tex]\frac{px+q}{(x+a)^2}=\frac{A}{x+a}+\frac{B}{(x+a)^2}[/tex]

[tex]\frac{px^2-qx+r}{(x+a)(x^2+bx+c)}=\frac{A}{x+a}+\frac{Bx+C}{x^2+bx+c}[/tex]


for your problem

[tex]\frac{x^2+8}{x^2-5x+6}[/tex]

by long division, we get [tex]1+\frac{5x+2}{x^2-5x+6}[/tex]

let's consider the 2nd part

[tex]\frac{5x+2}{x^2-5x+6}[/tex]

factor

[tex]\frac{5x+2}{(x-3)(x-2)}[/tex]

apply thing

[tex]\frac{5x+2}{(x-3)(x-2)}=\frac{A}{x-3}+\frac{B}{x-2}[/tex]

solve for A and B

cross multiply

5x+2=A(x-2)+B(x-3)

5x+2=Ax-2A+Bx-3B

match powers

5x=Ax+Bx

5=A+B

2=-2A-3B

adding twice of previous equation, we get

12=-B

B=12

5=A+B

5=A+12

-7=A


so expressed as partial fractions, it is[tex]\frac{x^2+8}{x^2-5x+6}=1-\frac{7}{x-3}+\frac{12}{x-2}[/tex]