Need help with the Commutator of the Hamiltonian-Position-Momentum.

[xp , H] where p=h/i*d/dx and H= -h^2/(2m)*d^2/dx^2 +V(x) ...... here is what i got:
[ x*h/i*d/dx , -h^2/(2m)*d^2/dx^2 +V ] *Y(x) where Y is my test function ill drop at the end.
=[ x*h/i*d/dx( -h^2/(2m)*d^2/dx^2 +V) -( -h^2/(2m)*d^2/dx^2 +V)*( x*h/i*d/dx)] *Y(x) =
=[ x*h/i*d/dx( -h^2/(2m)*d^2(Y)/dx^2 +V*Y) -( -h^2/(2m)*d^2/dx^2 +V)*( x*h/i*d(Y )/dx)] =
Doing the chain rule and multiplying out I get: Yxh/i*dV/dx….. but the answer has a second term 2vxh/i*dY/dx … any help would be appreciated.

Question

Need help with the Commutator of the Hamiltonian-Position-Momentum. 

[xp , H] where p=h/i*d/dx and H= -h^2/(2m)*d^2/dx^2 +V(x) ...... here is what i got: 
[  x*h/i*d/dx  , -h^2/(2m)*d^2/dx^2 +V ] *Y(x)  where Y is my test function ill drop at the end.
=[  x*h/i*d/dx(  -h^2/(2m)*d^2/dx^2 +V) -(  -h^2/(2m)*d^2/dx^2 +V)*( x*h/i*d/dx)] *Y(x)   =
=[  x*h/i*d/dx(  -h^2/(2m)*d^2(Y)/dx^2 +V*Y) -(  -h^2/(2m)*d^2/dx^2 +V)*( x*h/i*d(Y )/dx)] =
Doing the chain rule and multiplying out I get: Yxh/i*dV/dx….. but the answer has a second term 2vxh/i*dY/dx … any help would be appreciated.