Question #9c78e

1 Answer
Oct 16, 2017

#a=1,b=7,c=-3#.

Explanation:

Given,

#f(x)=x+a+b/(x+1)+c/(x+1)^2#

Now find out the LCM and add up all the terms.

#f(x)=(x(x+1)^2+a(x+1)^2+b(x+1)+c)/(x+1)^2#

#:.color(red)(f(x)=(x^3+(a+2)x^2+(2a+b+1)x+(a+b+c))/(x+1)^2)#.......(1).

Again given that,

#color(red)(f(x)=(x^3+3x^2+10x+5)/(x+1)^2)#.......(2).

Now, comparing the coefficients of these two equations we get three more equations #rarr#

#a+2=3#........(a).

#2a+b+1=10#........(b).

#a+b+c=5#........(c).

Now solving these three equations we get,

#color(red)(a=1,b=7,c=-3)#. (Answer).

Hope if Helps:)