Question

a funcao f (x)= x2 -4x +k tem o valor minimo igual a 8.qual o valor de k?

Answer 1

$Valor~Mi\´nimo= \frac{ - \alpha }{4a} = 8$

$\frac{-(16-4k)}{4} = 8~~~~~multiplica~~cruzado$
$-16 + 4k =32$
$4k = 32+16$
$4k = 48$
$k = \frac{48}{4}$

$\boxed {k= 12 }$