For the curve represented parametrically by
$$x = \ln(t^3 + 1), \quad y = \sin\pi t$$
where $t > 0$, find the value of $\frac{dy}{dx}$ at $t = 1$. [3 points]\\
(1) $-\frac{1}{3}\pi$\\
(2) $-\frac{2}{3}\pi$\\
(3) $-\pi$\\
(4) $-\frac{4}{3}\pi$\\
(5) $-\frac{5}{3}\pi$