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Derivative of $$$\ln\left(x^{2}\right)$$$
Related calculator: Derivative Calculator
Solution
The function $$$\ln\left(x^{2}\right)$$$ is the composition $$$f{\left(g{\left(x \right)} \right)}$$$ of two functions $$$f{\left(u \right)} = \ln\left(u\right)$$$ and $$$g{\left(x \right)} = x^{2}$$$.
Apply the chain rule $$$\frac{d}{dx} \left(f{\left(g{\left(x \right)} \right)}\right) = \frac{d}{du} \left(f{\left(u \right)}\right) \frac{d}{dx} \left(g{\left(x \right)}\right)$$$:
$${\color{red}\left(\frac{d}{dx} \left(\ln\left(x^{2}\right)\right)\right)} = {\color{red}\left(\frac{d}{du} \left(\ln\left(u\right)\right) \frac{d}{dx} \left(x^{2}\right)\right)}$$The derivative of the natural logarithm is $$$\frac{d}{du} \left(\ln\left(u\right)\right) = \frac{1}{u}$$$:
$${\color{red}\left(\frac{d}{du} \left(\ln\left(u\right)\right)\right)} \frac{d}{dx} \left(x^{2}\right) = {\color{red}\left(\frac{1}{u}\right)} \frac{d}{dx} \left(x^{2}\right)$$Return to the old variable:
$$\frac{\frac{d}{dx} \left(x^{2}\right)}{{\color{red}\left(u\right)}} = \frac{\frac{d}{dx} \left(x^{2}\right)}{{\color{red}\left(x^{2}\right)}}$$Apply the power rule $$$\frac{d}{dx} \left(x^{n}\right) = n x^{n - 1}$$$ with $$$n = 2$$$:
$$\frac{{\color{red}\left(\frac{d}{dx} \left(x^{2}\right)\right)}}{x^{2}} = \frac{{\color{red}\left(2 x\right)}}{x^{2}}$$Thus, $$$\frac{d}{dx} \left(\ln\left(x^{2}\right)\right) = \frac{2}{x}$$$.
Answer
$$$\frac{d}{dx} \left(\ln\left(x^{2}\right)\right) = \frac{2}{x}$$$A