Question

Se d = n(n − 3) , calcule o valor de d para n = 12.

Answer 1

$d=\dfrac{n(n-3)}{2}$

Fazendo n=12 na expressão temos:

$d=\dfrac{12(12-3)}{2}\\\\d=\dfrac{12\cdot9}{2}\\\\d=\dfrac{108}{2}\\\\\boxed{d=54}$