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A Glossary of Mathematical Terms - C


The branch of Maths that deals with the limits, differentiation and integration of functions and reelated topics.

Cardinal number

A "number" that tells us how many objects are in a set.


See Circle.


The set of all points on a plane whose distance from a fixed point (the center) is less than or equal to a given number (the radius -pl.radii);
circumference: the circle perimeter;
arc: the part of a circumference between to points; if you need to distinguish between the two arcs that share the same endpoints, the greatest is the major arc, the smallest is the minor arc;
chord: a segment whose endpoints are on the circumference;
central angle: an angle whose vertex is the center of the circle;
interior of a circle: the set of all points whose distance from the center is less than the radius;
sector: a part of a circle between two radii and an arc;
circular segment: a part of a circle between two chords or a chord and an arc;
semicircle: a sector whose central angle is 180°;
concentric circles: circles that have the same center.

Circle graph (Pie chart)

A graph of statistical data where a circle is subdivided into sectors that represent the percent of the total.


Used in orientation (the opposite is counterclockwise).


In operations between numbers: the outcome of the operation is in the same set as the operands.
In topology used as closure of a set.


Mainly the numerical part of a term in an algebraic expression.
Also used in other circumstances.

Coincidental lines

Two (or more) lines that are identical.


In the same line.


Arrangements of lists where the order is neither important nor significant.

Common factor

A common factor of two or more numbers is a number which is a factor of each of the two numbers.

Common multiple

A common factor of two or more numbers is a number which is a multiple of each of the two numbers.

Commutative law

The law states that when performing an operation on two or more objects, the order of objects does not affect the outcome. Addition and multiplication between numbers are commutative, subtraction and division are not commutative.


See Angle.

Complex number

A number that can be written as the some of a real and an imaginary number.

Composite integer

An integer that has two or more prime factors.


Used for angles (greater than 180°) and polygons (that have at least one concave angle).

Conditional sentence

A sentence of the form "if ... then ... ".


Two figures or shapes that have exactly the same size and shape.

Conic sections

The curves cut by a plane with a double cone: circle, ellipse, hyperbola, parabola, two intersecting lines, a point.


"In sequence": used is several contexts (consecutive numbers, consecutive segments, consecutive sides of a polygon, consecutive vertices of a polygon...).


In a conditional expression: the then part;
in a proportion: the second term of each ratio.


A size change, with coefficient less than 1.


Used for angles (lesser than 180°), polygons (whose angles are all convex), sets (a set of points in wich all segments connecting points of the set lie entirely in the set).


Within the same plane.

Corollary to a theorem

A theorem that easily follows from another theorem.


See Angle.


Used in orientation (the opposite is clockwise).

Counting numbers

The same as Natural numbers: {1,2,...} (see also Whole Numbers).


See Ordered pair.

Cube root

A number that, when raised to the power of 3 gives the original number.

Curly brackets { }

See Braces.

first published on september 01 2003 - last updated on september 01 2003