Differentiate each of the following from first principle: `(cos x)/x`

Explanation

To differentiate the function \( f(x) = \frac{\cos x}{x} \) using the first principle of derivatives, we follow these steps:

### Step 1: Write the definition of the derivative
The derivative of a function \( f(x) \) using the first principle is given by:
\[ f'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h} \]

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