(8x^3+7)/((x+1)(2x+1)^3)

I get 8x^3= A(2x+1)^6 + B(x+1)(2x+1)^5 + C(x+1)(2x+1)^4 + D(x+1)(2x+1)^3

i get a=-1 and b,c,d=-1/2

i then integrated each individual fraction and got the wrong answer.. somthing is wrong with my above step. can someone help me to solve it properly and why

any help is very appreciated