# Math Vocabulary - C

Word Definition Examples
Calculus The study of infinitely small changes in slope and area, used to solve complicated real-world problems that cannot be solved using Algebra, Geometry, or Trigonometry.

Calculus was invented by several mathematicians at about the same time, but Sir Isaac Newton gets most of the credit. He needed calculus to be able to solve problems in astronomy and physics.

Central angle An angle whose vertex is the center of a circle.

The minor arc is the small part of the circle cut off by the angle, and the major arc is the larger part of the circle. Centroid The point in a triangle where the medians of the triangle intersect. Click here for an animated example of the centroid. Central tendency The tendency of data to be grouped near the center of the data.Measured using mean, median, and mode. Certain Event An event whose probability is one (1) or 100% Something that always happens
Circle The set of all points in a plane that are a constant distance of r from a given point called the center.

On a coordinate graph (x-y graph), if the center is at (h,k) and the radius is r, the equation of the circle is

(x-h)2 + (y-k)2 = r2

(x-2)2 + (y-3)2 = 52 is a circle with center at (2,3) and a radius of 5 Circular function The trig functions, because they can be defined as points along the radius of the unit circle.
Circle Graph A graph that represents the frequency of data as slices of a circle. The size of each slice represents the frequency, usually recorded as a percent.

Also know as a Pie Chart because of the shape. Circumcenter The point in a triangle where the perpendicular bisectors of the sides of the triangle intersect. Click here for an animated example of the circumcenter. Closed interval An interval that includes both of its end points.

The example shows the closed interval from -3 to 1.
In math, we write this as [-3,1] and the square brackets mean that the end points are included. Coefficient The numerical factor when a term has a variable - a number that is multiplied by a variable in an equation or expression. The number next to a letter  5y
5 is the coefficient and y is the variable
Cofunction In trigonometry, the function pairs: sine and cosine, tangent and cotangent, and secant and cosecant.

The graphs of cofunctions are closely related to each other.

The example shows sin x and cos x on the same graph. Collinear Points that lie on the same line - 3 or more points that all line up

In the example, points A, B, C and D are collinear. Combination An arrangement or listing where the order is not important. Picking three students out of a classroom
Common factors Numbers, variables, and any products formed from the prime factors that appear in all terms of an expression For 2x2 -6x
2 and x are the common factors
because 2x times x equals 2x2
and 2x times -3 equals -6x
Common logarithm A base 10 logarithm, abbreviated log By definition: log 1 = 0
log 10 = 1
log 100 = 2
Commutative Property Changing the order of addends or factors does not change the sum or product Order doesn't matter when adding or multiplying 2 + 3 = 3 + 2 = 5

5 x 4 = 4 x 5 = 20

Compass A tool used in geometry to draw circles and parts of circles. Complementary angles Two positive angles whose measures add to 90 degrees

If two angle A and B add up to 90 (A + B = 90°) then A and B are complimentary. Completing the Square One method used to solve a quadratic equation. Other methods include factoring and the quadratic formula.
Complex fraction A fraction where the numerator, denominator, or both has a fraction Complex Number A number of the form a + bi, where a and b are real numbers and i is the square root of -1. Also called an imaginary number
Concave polygon When a diagonal contains points outside the polygon.
An "innie" Congruent Objects that are the same size and the same shape. The symbol for congruent is an equal sign with a squiggle over it. Conjecture The conclusion reached in a math statement based on reasoning - a guess based on observations.
Constant A value or number that never changes 5
-3.7
pi
Constant Term A term that has no variable factor - a number in an equation that is not multiplied by a variable A number that stands alone 7x + 3
3 is the constant term
Construction Using only a compass and a straight edge to draw a geometric figure.

An excellent animated version of some common constructions is available at Math is Fun

Continuous Data Measures that change between data points Things that could be measured at any time - they always exist temperature, height, time, blood pressure, average grade
Continuous Function Function whose graph is an unbroken curve - it does not have any holes, gaps, or jumps
While this is apparently simple, it is mathematically hard to explain, requiring Calculus. For this detail, visit Wolfram Math World
Convex polygon No diagonal contains points outside the polygon - all the vertices of the angles point away from the center of the polygon. Coordinate of a point On a number line, it is the distance of the point from the origin. On a coordinate axit is is the pair (x, y) that defines the location.
Coordinate pair A pair of numbers of the form (x, y) that gives the location of a point in the coordinate plane.
Coordinate Plane Formed when two number lines intersect at right angles. The x-axis is the horizontal axis and the y-axis is the vertical axis. The two axes meet at the origin (0,0). Click here for another explaination. Coplanar Points and lines that are in the same plane

The VLA west of Socorro, NM, is a group of 27 radio telescopes that are coplanar. Correlation A trend between two sets of data. A trend may show positive correlation (both sets of data get bigger together) negative correlation (one set of data gets bigger while the other gets smaller), or no correlation. Corresponding parts Matching sides and angles in a polygon. Corollary A statement that follows directly from a theorem. Once you prove a theorem, the corollary is easily proven.
Cosine The ratio of the length of the side adjacent to an angle and the hypotenuse in a right triangle side adjacent divided by hypotenuse see Trigonometry
Coterminal Angles Two angles that share two sides in standard position.

In the example, 30, -330, and 390 are alll coterminal angles. Cubic Equation An equation in the form
ax3 + bx2 + cx + d = y, where a, b, c, and d are real numbers and a ≠ 0
Largest exponent is 3 2x3 + 3x2 -5x + 7 = y
Cycloid A curve that represents a path traced by a fixed point on the circumference of a circle rolling along a line. Used in Trigonometry and Calculus. x = at - a sin t
y = a - a cos t
for t any real number (usually time)
Comments, questions, or you just need some help? Send an e-mail to Mrs. Shearer Last Updated: 06/14/2014