If a convergent beam of light passes through a diverging lens, the result 

For a converging beam incident on a concave lens ,$$\begin{gathered} \frac{1}{v}-\frac{1}{\left(+u\right)}=\frac{1}{\left(-f\right)}[Here the object is virtual object ] \\ \Rightarrow v = \frac{uf}{f-u} \\ For u<f ,v is positive .For u=f , v is infinity . \end{gathered}$$