Find \( \frac{d}{d x}(6 f(x)-19 g(x)) \)

To find the derivative of the expression \(6 f(x) - 19 g(x)\), we can apply the basic rules of differentiation. The derivative of a constant multiplied by a function can be taken simply by multiplying the constant by the derivative of the function. So, we get: \[ \frac{d}{dx}(6 f(x) - 19 g(x)) = 6 \frac{d}{dx}(f(x)) - 19 \frac{d}{dx}(g(x)). \] Thus, the derivative is: \[ 6 f'(x) - 19 g'(x). \]