I think you meant to say
and not "4 times y" on the right side (which would lead to a complex value for y when x = 0). Note that when x = 0, the equation reduces to ln(y) = 0, so that y = 1.
Implicitly differentiating both sides with respect to x, taking y = y(x), and solving for dy/dx gives
Note that when x = 0 and y = 1, we have dy/dx = 3.
Differentiate both sides again with respect to x :
No need to simplify; just plug in x = 0, y = 1, and dy/dx = 3 to get