How do you express (x^2+8)/(x^2-5x+6)x2+8x2−5x+6 in partial fractions?
1 Answer
Apr 21, 2016
Explanation:
(x^2+8)/(x^2-5x+6)x2+8x2−5x+6
=((x^2-5x+6)+(5x+2))/(x^2-5x+6)=(x2−5x+6)+(5x+2)x2−5x+6
=1+(5x+2)/(x^2-5x+6)=1+5x+2x2−5x+6
=1+(5x+2)/((x-2)(x-3))=1+5x+2(x−2)(x−3)
=1+A/(x-2)+B/(x-3)=1+Ax−2+Bx−3
=1+(A(x-3)+B(x-2))/(x^2-5x+6)=1+A(x−3)+B(x−2)x2−5x+6
=1+((A+B)x-(3A+2B))/(x^2-5x+6)=1+(A+B)x−(3A+2B)x2−5x+6
Equating coefficients we get:
{ (A+B=5), (3A+2B=-2) :}
Subtract twice the first equation from the second to find:
A = -12
Then substitute this value of
B = 17
So:
(x^2+8)/(x^2-5x+6)=1-12/(x-2)+17/(x-3)