Let $f:[0,\infty)\to\mathbb{R}$ be a differentiable function such that $f(x)=1-2x+\displaystyle\int_{0}^{x}e^{,x-t}f(t),dt$ for all $x\in[0,\infty)$. Then the area of the region bounded by $y=f(x)$ and the coordinate axes is