What are the focus and directrix of the parabola with the equation y = 1/12 x2.
Solution:
The equation of the parabola y = 1/12 x2
Vertex = (0, 0)
Vertex form equation of the parabola is
y = a (x - h)2 + k
By comparing the vertex form to the given equation
Vertex (h, k) = (0, 0)
Focus = (h, 1/4a)
h = 0
1/4a = 1 / [4(1/12)] = 3
Focus = (0, 3)
To find the directrix, the given equation can be written as
x2 = 12y
By comparing x2 = 12y with x2 = 4ay
4a = 12
Dividing both sides by 4
a = 3
We know that directrix is written as
y = -a
y = -3
Therefore, the focus and the directrix of the parabola are (0, 3) and y = -3.
What are the focus and directrix of the parabola with the equation y = 1/12 x2.
Summary:
The focus and directrix of the parabola with the equation y = 1/12 x2 are (0, 3) and y = -3.
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