$$$\sqrt{x} - 1$$$ 的導數
您的輸入
求$$$\frac{d}{dx} \left(\sqrt{x} - 1\right)$$$。
解答
和/差的導數等於導數的和/差:
$${\color{red}\left(\frac{d}{dx} \left(\sqrt{x} - 1\right)\right)} = {\color{red}\left(\frac{d}{dx} \left(\sqrt{x}\right) - \frac{d}{dx} \left(1\right)\right)}$$常數的導數為$$$0$$$:
$$- {\color{red}\left(\frac{d}{dx} \left(1\right)\right)} + \frac{d}{dx} \left(\sqrt{x}\right) = - {\color{red}\left(0\right)} + \frac{d}{dx} \left(\sqrt{x}\right)$$套用冪次法則 $$$\frac{d}{dx} \left(x^{n}\right) = n x^{n - 1}$$$,取 $$$n = \frac{1}{2}$$$:
$${\color{red}\left(\frac{d}{dx} \left(\sqrt{x}\right)\right)} = {\color{red}\left(\frac{1}{2 \sqrt{x}}\right)}$$因此,$$$\frac{d}{dx} \left(\sqrt{x} - 1\right) = \frac{1}{2 \sqrt{x}}$$$。
答案
$$$\frac{d}{dx} \left(\sqrt{x} - 1\right) = \frac{1}{2 \sqrt{x}}$$$A