Question

Which image shows a plane slicing a double-napped cone to produce a hyperbola? Answer is D

Answer 1

The second image in the diagram is a hyperbola. As can be seen, the plane cutting the cone can be at any angle but never equal to the slant angle of the cone. This has a very important implication. The plane cuts both cones of the double-napped cone. The third double-napped cone of Figure 3 shows two hyperbolas.