2.65: Differentiation and small change in a quotient

Differentiate $y = \tan(x + 4) - 3\sin x$ with respect to $x$.

Variables $x$ and $y$ are such that $y = \dfrac{\ln(2x + 5)}{2\mathrm{e}^{3x}}$. Use differentiation to find the approximate change in $y$ as $x$ increases from $1$ to $1 + h$, where $h$ is small.