Question

Se f(x)= x2 – 2, o resultado de f(3) é:
a) ( ) 4 b) ( ) 7 c) ( ) 9 d) ( ) 0

Answer 1

$f\left(x\right)=x2-2,\:\:f\left(3\right)\\\\=3^2-2\\\\3^2-2\\\\3^2=9\\\\=9-2\\\\\mathrm{Subtrair:}\:9-2=7\\\\=7$

b) ( X ) 7