(logic) In quantified modal logic, the formula ∀x□Fx→□∀xFx, meaning "if every x is necessarily F, then it is necessary that every x is F".

plural of infant formula

The empirical equation used to calculate the Balmer series.

(logic) A statement that is expressed in a valid, syntactically correct, manner.

plural of well-formed formula

plural of well-formed formula

(mathematics) A formula which when given a set of n points (x_i,y_i), gives back the unique polynomial of degree (at most) n − 1 in one variable which describes a function passing through those points. The formula is a sum of products, like so: ∑ᵢⁿy_i∏_(j ne i)x-x_j/x_i-x_j. When x=x_i then all terms in the sum other than the iᵗʰ contain a factor x-x_i in the numerator, which becomes equal to zero, thus all terms in the sum other than the iᵗʰ vanish, and the iᵗʰ term has factors x_i-x_j both in the numerator and denominator, which simplify to yield 1, thus the polynomial should return y_i as the function of x_i for any i in the set 1,...,n.

(mathematics) A mathematical formula relating the vertices, edges and faces of a polyhedron: V-E+F=2

(mathematics) A formula that connects trigonometry and complex numbers, stating that, for any complex number (and, in particular, for any real number) x and integer n, big ( cos (x)+i sin (x) big )ⁿ= cos (nx)+i sin (nx), where i is the imaginary unit.

(numerical analysis) Any of a group of formulas for numerical integration (quadrature) based on evaluating the integrand at equally spaced points.