Darcy friction factor - Swamee–Jain equation
Darcy's law
Bretschneider's formula - alternative version with diagonals
Bivariate (two variable) quadratic function(y minimum/maximum)
Speed of Sound in Fluids (Newton-Laplace equation )
Parallax
Disk area
Gain - Parabolic Antenna (also conical)
Ellipsoidal Coordinate ("z" cartesian coordinate)
Moment of inertia factor