RBSE SS Mathematics study materials
RBSE SS Mathematics study resources

RBSE SS Mathematics key terms

RBSE SS Mathematics · Get comfortable with the vocabulary.

Relation

A set of ordered pairs linking elements of one set to elements of another; the set of all first elements is the domain and the set of all second elements is the range.

Related: Function, Domain
Function

A relation in which every element of the domain is paired with exactly one element of the range, so no two ordered pairs share the same first coordinate.

Related: Relation, One-one Function, Onto Function
Domain

The complete set of input values for which a relation or function is defined; for a real function it is the set of real numbers giving a real output.

Related: Range, Function
Range

The set of all output values a function actually produces from its domain, distinct from the codomain which may contain unused elements.

Related: Domain, Onto Function
One-one Function

A function where distinct inputs always give distinct outputs, also called injective; equivalently, f(a) = f(b) forces a = b.

Related: Onto Function, Bijective Function
Onto Function

A function whose range equals its codomain, so every element of the codomain is the image of at least one domain element; also called surjective.

Related: One-one Function, Bijective Function
Bijective Function

A function that is both one-one and onto; only such functions possess an inverse function defined on the whole codomain.

Related: One-one Function, Onto Function, Invertible Function
Composite Function

A function formed by applying one function to the output of another, written (g∘f)(x) = g(f(x)); its domain must satisfy both functions' restrictions.

Related: Invertible Function, Function
Invertible Function

A function that has an inverse, which happens exactly when it is bijective; the inverse reverses each ordered pair, so f⁻¹(y) = x whenever f(x) = y.

Related: Bijective Function, Composite Function
Principal Value Branch

A restricted range chosen for an inverse trigonometric function so it becomes one-one and onto, giving a single agreed output for each input.

Related: Inverse Trigonometric Function, One-one Function
Inverse Trigonometric Function

The inverse of a trigonometric function, defined on a restricted domain with a principal value range, for example sin⁻¹x with range from minus pi by two to pi by two.

Related: Principal Value Branch, Domain
Matrix

A rectangular arrangement of numbers in rows and columns, enclosed in brackets; an m by n matrix has m rows and n columns and order m×n.

Related: Order of a Matrix, Transpose of a Matrix
Order of a Matrix

The pair stating how many rows and columns a matrix has, written rows first then columns; it fixes which matrix operations are possible with another matrix.

Related: Matrix, Matrix Multiplication
Transpose of a Matrix

The matrix obtained by interchanging rows and columns, denoted Aᵀ; transposing twice returns the original matrix, and (AB)ᵀ = BᵀAᵀ.

Related: Symmetric Matrix, Skew-symmetric Matrix
Symmetric Matrix

A square matrix equal to its own transpose, so entry aᵢⱼ equals aⱼᵢ for all positions; its entries mirror across the main diagonal.

Related: Skew-symmetric Matrix, Transpose of a Matrix
Skew-symmetric Matrix

A square matrix whose transpose is its negative, so aᵢⱼ = −aⱼᵢ; every diagonal entry must be zero, and adding such a matrix to its transpose gives the zero matrix.

Related: Symmetric Matrix, Transpose of a Matrix
Determinant

A single number computed from a square matrix that tells whether the matrix is invertible and how it scales areas or volumes; it is zero for singular matrices.

Related: Singular Matrix, Adjoint of a Matrix, Cramer's Rule
Singular Matrix

A square matrix whose determinant equals zero, so it has no inverse and its rows or columns are linearly dependent.

Related: Determinant, Adjoint of a Matrix
Adjoint of a Matrix

The transpose of the cofactor matrix of a square matrix, used in the formula A⁻¹ = adj(A)/|A| when the determinant is nonzero.

Related: Determinant, Singular Matrix
Cramer's Rule

A method solving a square system of linear equations by writing each unknown as a ratio of two determinants, valid only when the coefficient determinant is nonzero.

Related: Determinant, Consistent System
Consistent System

A system of linear equations that has at least one solution; it has a unique solution when the coefficient determinant is nonzero and infinitely many when the system is dependent.

Related: Cramer's Rule, Determinant
Continuity

A property of a function at a point where the left limit, right limit and function value all exist and are equal; graphically the curve has no break there.

Related: Differentiability, Limit
Differentiability

A property of a function at a point where the derivative exists as a finite limit of the difference quotient; differentiability at a point implies continuity there, but not conversely.

Related: Continuity, Derivative
Derivative

The instantaneous rate of change of a function with respect to its variable, defined as the limit of the difference quotient; geometrically it gives the slope of the tangent.

Related: Differentiability, Critical Point
Critical Point

An interior point of a function's domain where the derivative is zero or fails to exist; candidates for local maxima, local minima or points of inflection.

Related: Derivative, Point of Inflection
Point of Inflection

A point where the concavity of a curve changes sign, typically where the second derivative is zero or undefined while the curve remains continuous.

Related: Critical Point, Concavity
Concavity

The way a curve bends: concave up when the second derivative is positive and concave down when it is negative, determined on intervals of the domain.

Related: Point of Inflection, Derivative
Indefinite Integral

The family of all antiderivatives of a function, written with an arbitrary constant of integration because differentiating any member returns the original function.

Related: Definite Integral, Integration by Parts
Definite Integral

The limit of a sum over a closed interval, interpreted as the signed area between a curve and the axis; it is a number found using the fundamental theorem of calculus.

Related: Indefinite Integral, Area Under a Curve
Integration by Parts

A technique based on the product rule, written as the integral of u dv equals uv minus the integral of v du, used when an integrand is a product of unlike functions.

Related: Indefinite Integral, Partial Fraction Decomposition
Partial Fraction Decomposition

Rewriting a rational integrand as a sum of simpler fractions with linear or quadratic denominators, so each part can be integrated by standard formulas.

Related: Integration by Parts, Indefinite Integral
Area Under a Curve

The region bounded by a curve, the horizontal axis and two vertical lines, computed as a definite integral; portions below the axis count as negative unless absolute values are used.

Related: Definite Integral
Differential Equation

An equation involving an unknown function and one or more of its derivatives, classified by order and degree and solved by finding a function satisfying it.

Related: Order of a Differential Equation, General Solution
Order of a Differential Equation

The order of the highest derivative appearing in the equation; a first-order equation involves only the first derivative of the unknown function.

Related: Differential Equation, Degree of a Differential Equation
Degree of a Differential Equation

The power of the highest-order derivative after the equation is cleared of radicals and fractions in derivatives; defined only for polynomial equations in derivatives.

Related: Order of a Differential Equation, Differential Equation
General Solution

The solution of a differential equation containing as many arbitrary constants as the order of the equation, representing a whole family of curves.

Related: Particular Solution, Differential Equation
Particular Solution

A solution obtained from the general solution by assigning specific values to the arbitrary constants, usually fixed by given initial conditions.

Related: General Solution, Differential Equation
Integrating Factor

A multiplier, for a first-order linear equation dy/dx + Py = Q it equals e to the integral of P dx, that makes the left side an exact derivative.

Related: Differential Equation, General Solution
Vector

A quantity having both magnitude and direction, represented by a directed line segment and written in component form with unit vectors along the axes.

Related: Unit Vector, Dot Product, Cross Product
Unit Vector

A vector of magnitude one, often used to give direction; any nonzero vector divided by its own magnitude becomes a unit vector in the same direction.

Related: Vector, Direction Cosines
Dot Product

The scalar obtained from two vectors as the product of their magnitudes and the cosine of the angle between them; it is zero when the vectors are perpendicular.

Related: Cross Product, Vector
Cross Product

A vector perpendicular to two given vectors with magnitude equal to the product of their magnitudes and the sine of the angle between them; it vanishes for parallel vectors.

Related: Dot Product, Scalar Triple Product
Scalar Triple Product

The dot product of one vector with the cross product of two others; its absolute value gives the volume of the parallelepiped formed by the three vectors.

Related: Cross Product, Dot Product
Direction Cosines

The cosines of the angles a line makes with the positive coordinate axes, usually denoted l, m and n; their squares sum to one.

Related: Unit Vector, Vector
Linear Programming Problem

An optimisation problem seeking the maximum or minimum of a linear objective function subject to linear inequality constraints and non-negativity restrictions.

Related: Feasible Region, Objective Function, Corner Point Method
Feasible Region

The set of all points satisfying every constraint of a linear programming problem simultaneously; it is usually a convex polygon in the first quadrant.

Related: Linear Programming Problem, Corner Point Method
Objective Function

The linear expression whose value is to be maximised or minimised in a linear programming problem, evaluated at the corner points of the feasible region.

Related: Feasible Region, Corner Point Method
Corner Point Method

A procedure solving a linear programming problem by evaluating the objective function at each vertex of the feasible region, since the optimum occurs at a vertex when it exists.

Related: Feasible Region, Objective Function
Conditional Probability

The probability of an event given that another event has already occurred, written P(A|B) and equal to P(A intersection B) divided by P(B) when P(B) is nonzero.

Related: Independent Events, Bayes' Theorem
Independent Events

Two events whose occurrence does not affect each other's probability; equivalently, the probability of both equals the product of their separate probabilities.

Related: Conditional Probability, Mutually Exclusive Events
Mutually Exclusive Events

Two events that cannot occur together, so their intersection is empty and the probability of either equals the sum of their probabilities.

Related: Independent Events, Conditional Probability
Bayes' Theorem

A rule reversing a conditional probability, expressing P(A|B) in terms of P(B|A), the prior probability of A and the total probability of B.

Related: Conditional Probability, Theorem of Total Probability
Theorem of Total Probability

A rule giving the probability of an event as the sum of its conditional probabilities over a partition of the sample space into mutually exclusive exhaustive events.

Related: Bayes' Theorem, Conditional Probability
Random Variable

A real-valued function defined on the sample space of an experiment, assigning a number to each outcome so probabilities can be described numerically.

Related: Probability Distribution, Bernoulli Trials
Bernoulli Trials

Repeated independent trials of an experiment with exactly two outcomes, success or failure, where the probability of success stays constant in every trial.

Related: Random Variable, Binomial Distribution
Binomial Distribution

The probability distribution of the number of successes in a fixed number of independent Bernoulli trials, with formula nCr p^r q^(n−r) for r successes.

Related: Bernoulli Trials, Random Variable
Portfolio

A organised collection of a student's mathematical work, such as solved problems, notes and reflections, assessed for understanding, effort and consistent record-keeping.

Related: Mathematics Project
Mathematics Project

An extended independent investigation applying syllabus mathematics to a real situation, presented with aim, method, data, analysis and conclusion, and assessed on process as well as result.

Related: Portfolio