Question

If f(x, y, z)=sin(3x-yz), where x=e^(t-1), y=t^3, z=t-2, what's df/dt(1)? x(1)=1, y(1)=3, z(1)=-1, (3cos(3x-yz))(e^(t-1))+(cos(3x-z))(3t^2)+(cos(3x-y))(1)=(3cos(3x-yz))(e^0)+(cos(3x-z))(3)+(cos(3x-y))=(3cos(3x-yz))+(3cos(3x-z))+(cos(3x-y)) What do I do next?