Posted by
**Keira** on
.

Help me on this one :(

Express y= (7-3x-x^2)/[((1-x)^2)(2+x)] in partial fractions. Hence, prove that if x^3 and higher powers of x may be neglected, then y=(1/8)(28+30x+41x^2)

I did the first part of expressing it in partial fractions. (Since it's very difficult to type out fractions... i'll write it in terms of powers)

2(1-x)^(-1) + (1-x)^(-2) + (2+x)^(-1)

So i did a binomial on each of the three terms (fractions) above, neglecting anything after power 2. And then i added the three binomial expressions of each of the fractions, and what i got was (5 + 3x + 5.5x^2 + ...) This is different from what im supposed to prove!! Where did i go wrong?????!