invariant

the quantity B2−4AC is invariant under a rotation of axes. The distance between two points and the angle between two lines are invariants under translations and rotations of the plane, but distance is not invariant under dilations, while angle is.

• finite‐dimensional
• finitism
• first derivative
• first fundamental form
• first isomorphism theorem
• first-order logic
• first principles
• first‐order differential equation
• Fisher's exact test
• Fisher, Sir Ronald Aylmer
• fit
• fixed point
• fixed-point theorem
• fixed‐point iteration
• fixed‐point notation
• flag
• flat angle
• flex
• floating‐point notation
• float of an activity
• floor
• fluent
• fluid mechanics
• flux
• fluxion