Ok this is driving me nuts so I hope someone can help!
I am using partial fraction decomposition of this to find the A, B and C. So and thus
When I use the sub values in for S method, I am subbing in a 0 for the S, and this gets me 12=4A so A=3. BUT when you do it with the expand and compare method, I get A=8.
Where am I going wrong here??