You can expand the stuff on the right and then equate like terms. You'll get a system of equations.
Find the constants A, B and C for:
I tried to isolate the constants by substituting strategic values of x. For example:
Let x = -1,
C = -2
Let x = 1,
A = 1
However, I cannot isolate B. I'm sure this question is trivial and my brain is still in holiday mode. Any assistance would be most welcome.