Consider a triangle $ABC. A$ circle is drawn touching the incircle of the triangle $ABC$, side $AC$ extended and side $BC$. Let the radius of this circle be $r_{\mathrm{A}}$. Similarly $r_B$ and $r_C$ are radii of circles touching incircle, $BA$ extended and $CB$ extended as well as $AC$ and $AB$ respectively, $r$ is the radius of incircle and 

$r_1, r_2$ and $r_3$ are exradii of $∆ABC$.