# Tag Info

Your proposed title is Showing $\frac{|\overrightarrow{A_1B}|}{|\overrightarrow{A_1C}|}\frac{|\overrightarrow{B_1C}|}{|\overrightarrow{B_1A}|}\frac{|\overrightarrow{C_1A}|}{|\overrightarrow{C_1B}|}=1$ implies $AA_1$, $BB_1$, $CC_1$ concur (215 characters). Since \newcommand is now local, I believe it is safe to do [Edit: as per Martin's comment, this may ...