Final answer:
The focus of the parabola y=3x^2+12x+11 is located at a distance of 1/12 units from the vertex.
Step-by-step explanation:
The equation y = 3x^2 + 12x + 11 represents a parabola. To find the focus of the parabola, we first need to convert the equation into the standard form y = a(x - h)^2 + k. Comparing the given equation with the standard form, we can see that a = 3, h = -12/6 = -2, and k = 11 - (3(-12/6)^2) = 5.
The vertex of the parabola is given by (h, k), which in this case is (-2, 5). The focus of the parabola is located at a distance p = 1/(4a) units from the vertex. Substituting the value of a, we get p = 1/(4(3)) = 1/12.
Therefore, the correct answer is d. 1/12.