Find the derivative of the function `sec x. tan x` with respect to 'x'.

Explanation

To find the derivative of the function \( y = \sec x \cdot \tan x \) with respect to \( x \), we will use the product rule of differentiation. The product rule states that if you have two functions \( u \) and \( v \), then the derivative of their product is given by:

\[ \frac{dy}{dx} = u'v + uv' \]

where \( u' \) is the derivative of \( u \) and \( v' \) is the derivative of \( v \).

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