Mathematics. Dictionary

Random variable · R

A quantity whose value is random and to which a probability distribution is assigned, such as the possible outcome of a roll of a dice.

Rational function · R

Any function expressible as the quotient of two (coprime) polynomials (and which thus has poles at a finite, discrete set of points which are the roots of the denominator).

Real analysis · R

The branch of mathematics dealing with the real numbers and related structures.

Recurrence relation · R

an equation that recursively defines a sequence; each term of the sequence is defined as a function of the preceding terms.

Regular polygon · R

A polygon which is both equiangular and equilateral (i.e. having all sides the same length and all interior angles the same).

Relative frequency · R

The number of data points satisfying something divided by the total number of data points.

Right-hand rule · R

A common mnemonic for understanding notation conventions for vectors in three dimensions.

Row echelon form · R

The stepped appearance of a matrix that has undergone with the result that the leading coefficient or pivot (that is, the first nonzero number from the left) of a nonzero row is to the right of the pivot of the row above it.

Row space · R

The vector space generated by all the row vectors of a matrix.