Question

express y=((3x)^2)/(x-1)^2 in partial fractions. Hence, find the value of d^2y/dx^2 when x=2.

Answer 1

http://www.wolframalpha.com/input/?i=%289+x^2%29%2F%28-1+%2B+x%29^2

Answer 2

As you can see the above link
\[
\frac{9 x^2}{(x-1)^2}=\frac{9}{(x-1)^2}+\frac{18}{x-1}+9
\]
Can you finish it now?