设 $y=y(x)$ 由 $\left\{\begin{array}{l}x=t^3+2 t+1 \\ t-\int_1^{y+t} \mathrm{e}^{-u^2} \mathrm{~d} u=0\end{array}\right.$ 确定, 求 $\left.\frac{\mathrm{d} y}{\mathrm{~d} x}\right|_{t=0},\left.\frac{\mathrm{d}^2 y}{\mathrm{~d} x^2}\right|_{t=0}$.
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