To determine the derivative of the function \( f(x) = x^2 + 3x \), the power rule of differentiation is applied. The power rule is stated as:
\(\frac{d}{dx}[x^n] = nx^{n-1}\)
Applying the power rule to each component of \( f(x) \):
1. For the term \(x^2\):
\(\frac{d}{dx}[x^2] = 2x^{2-1} = 2x\)
2. For the term \(3x\):
\(\frac{d}{dx}[3x] = 3\)
Consequently, the derivative \( f'(x) \) is found by differentiating each term and summing the results:
\(f'(x) = 2x + 3\)
Therefore, the derivative is \(2x + 3\).