Respuesta :

dalendrk
f(x) = 3x² + 6x + 3 = 3(x² + 2x + 1) = 3(x + 1)² + 0

used: (a + b)² = a² + 2ab + b²

The vertex form: y = a(x - h)² + k
the coordinates of vertex: (h; k)

Therefore, your answer: (-1; 0).