If in a right angled triangle $\mathrm{ABC}$, the hypotenuse $|\overrightarrow{A B}|=p$ then $\overline{A B}…
If in a right angled triangle $\mathrm{ABC}$, the hypotenuse $|\overrightarrow{A B}|=p$ then $\overline{A B} \cdot \overline{A C}+\overline{B C} \cdot \overline{B A}+\overline{C A} \cdot \overline{C B}=$