How do you express # (3x+18)/(x^2+5x+4)# in partial fractions?
1 Answer
Aug 15, 2016
Explanation:
#(3x+18)/(x^2+5x+4)#
#=(3x+18)/((x+1)(x+4))#
#=A/(x+1)+B/(x+4)#
Use Heaviside's cover-up method to find:
#A = (3(-1)+18)/((-1)+4) = 15/3 = 5#
#B = (3(-4)+18)/((-4)+1) = 6/(-3) = -2#
So:
#(3x+18)/(x^2+5x+4)=5/(x+1)-2/(x+4)#
