Is it mathematically correct to say that $$\frac{d}{dt}(a+bi) = if(t)(a+bi)$$ implies that $$(a+bi) = Ne^{ig(t)}$$ where $N$ is a complex constant and $\frac{d}{dt}{g}=\frac{f}{N}$?
I'm just not sure whether the reasoning is sound because of the complex nature of the functions