Let y=y(x) be the solution of the differential equation (d y)/(d x)+2 y=f(x), where f(x)= {1, x ∈[0,1]; 0, otherwise} If y(0)=0, then y(3/2) is:

Let $\displaystyle y=y(x)$ be the solution of the differential equation $\displaystyle \frac{\mathrm{d} y}{\mathrm{~d} x}+2 y=f(x)$, where $\displaystyle f(x)= \begin{cases}1, & x \in[0,1] \\ 0, & \text { otherwise }\end{cases}$If $\displaystyle y(0)=0$, then $\displaystyle y\left(\frac{3}{2}\right)$ is :