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Derivative of $$$\ln\left(x^{3}\right)$$$
Related calculator: Derivative Calculator
Solution
The function $$$\ln\left(x^{3}\right)$$$ is the composition $$$f{\left(g{\left(x \right)} \right)}$$$ of two functions $$$f{\left(u \right)} = \ln\left(u\right)$$$ and $$$g{\left(x \right)} = x^{3}$$$.
Apply the chain rule $$$\frac{d}{dx} \left(f{\left(g{\left(x \right)} \right)}\right) = \frac{d}{du} \left(f{\left(u \right)}\right) \frac{d}{dx} \left(g{\left(x \right)}\right)$$$:
$$\frac{d}{dx} \left(3 \ln\left(x\right)\right) = \frac{d}{dx} \left(3 \ln\left(x\right)\right)$$The derivative of the natural logarithm is $$$\frac{d}{du} \left(\ln\left(u\right)\right) = \frac{1}{u}$$$:
$$\frac{d}{dx} \left(3 \ln\left(x\right)\right) = \frac{d}{dx} \left(3 \ln\left(x\right)\right)$$Return to the old variable:
$$\frac{d}{dx} \left(3 \ln\left(x\right)\right) = \frac{d}{dx} \left(3 \ln\left(x\right)\right)$$Apply the constant multiple rule $$$\frac{d}{dx} \left(c f{\left(x \right)}\right) = c \frac{d}{dx} \left(f{\left(x \right)}\right)$$$ with $$$c = 3$$$ and $$$f{\left(x \right)} = \ln\left(x\right)$$$:
$${\color{red}\left(\frac{d}{dx} \left(3 \ln\left(x\right)\right)\right)} = {\color{red}\left(3 \frac{d}{dx} \left(\ln\left(x\right)\right)\right)}$$The derivative of the natural logarithm is $$$\frac{d}{dx} \left(\ln\left(x\right)\right) = \frac{1}{x}$$$:
$$3 {\color{red}\left(\frac{d}{dx} \left(\ln\left(x\right)\right)\right)} = 3 {\color{red}\left(\frac{1}{x}\right)}$$Thus, $$$\frac{d}{dx} \left(\ln\left(x^{3}\right)\right) = \frac{3}{x}$$$.
Answer
$$$\frac{d}{dx} \left(\ln\left(x^{3}\right)\right) = \frac{3}{x}$$$A