consider the non homogeneous heat equation :
let $f:\mathbb{R}^n\times \mathbb{R}^+ \rightarrow \mathbb{R}$ be a smooth function
$\frac{\partial u}{\partial t}-\Delta u = f(x,t)$ , $x\in\mathbb{R}^n,t\in\mathbb{R}$
$u(x,0)=0$
so can someone tell me how to verify that the solution of this equation is given by :
$u(x,t)=\int_0^t(\int_{\mathbb{R}^n}\phi_n(x-y,t-s)f(y,s)dy)ds$
where $\phi_n$ is the fundamentale solution of the homogeneous heat equation.
thank you very much.