Let

Put


A(x+1)(x2+1)+B(x2+1)+(Cx+D)(x+1)2=1


Put x+1=0


X=-1


A(0)+B(1+1)+0=1



By equating the coefficient of x2 and constant term, A+C=0


A+B+2C=0……(2)



A+B+D=1


Solving (2) and (3),we get,





1