Respuesta :

[tex]6!=1\cdot2\cdot3\cdot4\cdot5\cdot6=720\\\\ 6P5=\dfrac{6!}{1!}=6!=720\\\\ 12C3=\dfrac{12!}{3!9!}=\dfrac{10\cdot11\cdot12}{2\cdot3}=220[/tex]