i'm not sure how to evaluate this

Question

(6)/(X^-4) + (5)/(X^-2)

Answer 1

the common denominator would be
(x^2-4(x^2-2), so

(6)/(X^-4) + (5)/(X^-2)
= [6(x^2-2) + 5(x^2-4)]/[(x^2-4(x^2-2)]
= (11x^2 - 32)/[(x^2-4(x^2-2)]

(are you sure the second denominator wasn't (x-2) ?
it would have worked much better)