What is wrong in my calculation ($x^{-1} \cdot \sqrt[3]{x} = ?$)?

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I need to calculate the following product:

$x^{-1} \cdot \sqrt[3]{x} = ?$

First, I apply the rule

$\sqrt[n]{x^m} = x^{\frac{m}{n}}$

to convert $\sqrt[3]{x}$ to $x^{\frac{1}{3}}$:

$x^{-1} \cdot \sqrt[3]{x} = x^{-1} \cdot x^{\frac{1}{3}}$

Then I add the exponents:

$x^{-1} \cdot \sqrt[3]{x} = x^{(-\frac{3}{3} + \frac{1}{3})}$

$x^{-1} \cdot \sqrt[3]{x} = x^{-\frac{2}{3}}$

I use the rule

$a^{-\frac{m}{n}} = \frac{1}{\sqrt[n]{a^m}}$

to transform $x^{(-\frac{2}{3})}$ to $\frac{1}{\sqrt[3]{x^2}}$.

However, if I check the solution by setting $x=1$ and calculating both sides, it turns out that it wrong.

Where exactly (in which of the above steps) did I make the error?