Differentiate each of the following from first principle: `tan^2x`

Explanation

To differentiate the function \( f(x) = \tan^2 x \) using the first principle, we will follow these steps:

### Step 1: Write the definition of the derivative using the first principle.
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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