Answer:
a) opens down
c) directrix at y = 1/8
d) vertex at (-1/2,0)
Explanation:
Starting from the given equation:
4x^2 + 4x + 2y + 1 = 0
We can rearrange to obtain the standard form of the equation of a parabola:
2(y + 1/2) = -4(x + 1/2)^2 + 1
(y + 1/2) = -2(x + 1/2)^2 + 1/2
Comparing to the standard form:
(y - k) = a(x - h)^2
We can see that the vertex of this parabola is at the point (-1/2, -1/2).
Next, we can find the axis of symmetry by noting that the parabola is symmetric about a vertical line passing through the vertex. This line is given by:
x = -1/2
We can also determine whether the parabola opens upward or downward by looking at the sign of the coefficient a. In this case, a = -2, so the parabola opens downward.
The distance between the vertex and the directrix is given by |1/(4a)|. Therefore, the distance between the vertex (-1/2, -1/2) and the directrix is:
|1/(4(-2))| = 1/8
So the directrix of the parabola is the horizontal line y = 1/8.
Therefore, the correct options are:
a) opens down
c) directrix at y = 1/8
d) vertex at (-1/2,0)
The other options are incorrect:
b) The parabola does not open to the left.
e) The directrix is not a vertical line at x = -3/8.