Question

fatorial de 15! sobre 13!

Answer 1

 15.14.13/13 a partir do 13 nao precisa calcular pois ele anula o 13 denominador. fica apenas 15x14= 210 

Answer 2

Dada a propriedade:

$\mathsf{n!=n\cdot \left(n-1\right)\cdot \left(n-2\right)\cdot ...\cdot 3\cdot 2\cdot 1}$

= = = = =

Logo:

$\mathsf{=\dfrac{15!}{13!}}\\\\\\\mathsf{=\dfrac{15\cdot 14\cdot \diagup\!\!\!\!\!\!13!}{\diagup\!\!\!\!\!\!13!}}\\\\\mathsf{=15\cdot 14}\\\\\mathsf{=\boxed{\mathsf{210}}}\: \: \checkmark$