If three equal charges are placed on three corners of square and force between $q_1$ and $q_2$ is $F_2$, and the force between $q_1$ and $q_2$ is $F_3$, find $F_3/F_2$

Question

$\begin{array}{1 1} q_3 /q_2 \\ q_3.q_2 \\ 2 \\ 1/2 \end{array}$