# 微積分筆記
* 基本微分法則：
1. $$
\begin{align}
f(x) &= ax^n \\
f^{\prime}(x) &= n \cdot ax^{n-1}
\end{align}
$$
2. $$
\frac{d}{dx}[ f(x) \pm g(x) ] = f^{\prime}(x) \pm g^{\prime}(x)
$$
3. $$
\frac{d}{dx}[f(x)g(x)] = f^{\prime}(x)g(x) + f(x)g^{\prime}(x)
$$
4. $$
\frac{d}{dx} \left( \frac{f(x)}{g(x)} \right) = \frac{ f^{\prime}(x)g(x) - f(x)g^{\prime}(x) }{\left[ g(x) \right] ^ 2}
$$