Differential Equations

The integrating factor for the first-order linear differential equation $\frac{dy}{dx} + P(x) y = Q(x)$ is given by:

Options:

• (A) $e^{\int P(x)\, dx}$
• (B) $e^{-\int Q(x)\, dx}$
• (C) $\int P(x)\, dx$
• (D) $P(x) Q(x)$