L27_A
1. Review: Gauss Curvature of a Surface of Revolution
2. Derivation: Differential Equation of the Asymptotic Curves
L27_B
1. Proposition: The Coordinate Curves Are Asymptotic Curves if and only
if e=g=0
2. Example: Asymptotic Curves
L27_C
1. Example: Asymptotic Curves (cont.)
2. Proposition: The Coordinate Curves Are Asymptotic Curves
if and only if f=F=0