The correct option is B 12(x−1)4+74(x−1)3+178(x−1)2+1516(x−1)+116⋅1(x+1)
Let x−1=y, i.e., x=1+y
∴x4(x−1)4(x+1)=(1+y)4y4(1+y+1)
=1+4y+6y2+4y3+y4y4(2+y)
Divide 1+4y+6y2+4y3+y4 by 2+y and continue till the remaider is y4.
2+y1+4y+6y2+4y3+y4⇂12+74y+178y2+1516y3
1+12y
−−
__________________
72y+6y2
72y+76y2
−−
_____________________
174y2+4y3
174y2+178y3
−−
________________________
158y3+y4
158y3+1516y4
−−
___________________
116y4
∴1+4y+6y2+4y3+y4(2+y)=⎡⎣12+74y+178y2+1516y3+116y42+y⎤⎦
∴(1+4y+6y2+4y3+y4y4(2+y)=12y4+74y3+178y2+1516y+116⋅12+y
in last putting y=x−1
∴x4(x−1)4(x+1)=12(x−1)4+74(x−1)3+178(x−1)2+1516(x−1)+116⋅1(x+1)
which are the required partial fractions.