Skip to main content
A three dimensional plot with axes labeled \(x\text{,}\) \(y\text{,}\) and \(z\text{.}\) A hyperboloid of two sheets with gap along the z-axis is drawn in gray with a point on the top sheet highlighted in red. At the highlighted point, a titled plane is shown, in red, such that the plane is tangent to the hyperboloid at the highlighted point. The highlighted point has a vector drawn perpendicular to the surface and pointing away from the z-axis.