Find the derivative of cos x from first principle.

Explanation

To find the derivative of \( \cos x \) from first principles, we will follow these steps:

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

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