What degenerate form or forms of the parabola CANNOT be obtained from the intersection of a plane and a double napped cone? I have to use a diagram and give complete description how to obtain this ( or these) form(s)

but what diagram would i use???

To answer this question and provide a diagram, you can use a standard coordinate grid or a graphing software that allows you to plot equations. When considering the intersection of a plane and a double-napped cone, we can obtain various forms of the parabola, but there are some degenerate forms that cannot be derived from this intersection.

Here's how you can approach finding the degenerate forms of the parabola:

1. Start with a standard coordinate grid, drawing the x and y axes.

2. Draw the double-napped cone by sketching two symmetrical parabolic curves facing each other with their vertex at the origin. You can represent this by plotting several points on each curve and then connecting them smoothly to form the curves.

3. To find the intersection of the plane and the cone, draw a straight line on the grid that intersects the cone. This line represents the plane.

4. Observe the intersection points between the line (plane) and the cone. As the line moves, it will intersect the cone at various locations, creating different forms of the parabola.

5. Now, identify the different types of parabolas that can be obtained from the intersection. Typical forms include upward-opening, downward-opening, rightward-facing, and leftward-facing parabolas.

6. To find the degenerate forms of the parabola, you're looking for special cases where the intersection does not yield a regular parabolic curve. For example:

a. A vertical line passing through the vertex of the cone will result in a degenerate form known as a "point." The intersection will only be a single point rather than a curve.

b. A horizontal line that intersects the cone at its vertex will create a degenerate form called a "line." The intersection will be a straight line rather than a curved parabola.

c. Similarly, if the plane is parallel to the axis of symmetry of the cone, the intersection will yield a degenerate form known as a "pair of parallel lines." The intersection will be two parallel lines instead of a curved parabola.

7. Label each form you identified on the diagram accordingly.

Remember, the diagram is a visual aid to help you understand and illustrate the different forms of parabolas that can be obtained from the intersection of a plane and a double-napped cone.