parabolic partial differential equation

where A,B,C,D,E,F,G are functions of x and y is parabolic, elliptic, or hyperbolic when B2–4AC is zero, negative, or positive, respectively. So the heat equation is parabolic, Laplace's equation is elliptic, and the wave equation is hyperbolic.

• radius
• radius
• radius of convergence
• radius of curvature
• radius of gyration
• radius vector
• raise
• Ramanujan, Srinivasa
• Ramsey, Frank
• Ramsey Theory
• random
• random error
• random graph
• randomization
• randomize
• randomized blocks
• random numbers
• random sample
• random variable
• random vector
• random walk
• range
• range
• range
• rank