Decimal
number
A number written
in the placevalue notation with base 10. For example 5.321
Decimal
notation
The method of
positional notation used in real number system. A real number can
be either rational or irrational. A rational number can be written
as a terminating decimal or repeating decimal number. For example,
3/4 = 0.75 is a terminating decimal number and
is a repeating decimal number where 3 is repeating forever and never
ending. Howeveris
an irrational number which is neither terminating nor repeating.
Decimal
system
A number system
using base ten.
Degree
A degree is
a measure of angle forming by two rays. A complete revolution is
360^{o}. therefore the measure of a right angle is 90^{0. }
Radian is a different measure of angle, in which is
the measure of a complete revolution. allows
us to convert from one measure to the other.
Denominator
The bottom number
(or expression) in a fraction. For example, in the fraction, 3/5,
5 is the denominator.
See Fraction.
Degree
of a monomial
The degree of
a monomial in one variable is the value of the exponent of the variable.
The degree of a monomial with more than one variable is the sum
of the exponents of the variables in that monomial. For example
in 4x^{2}y^{3}z , x has degree 2 ,
y degree 3 and z degree 1. The degree of the
whole term is the sum of these exponents, in this case 2+3+1
= 6.
Degree
of a polynomial
The degree of
a polynomial is the degree of the nonzero term with the highest
degree. For instance, x+xy+2y+5 is a polynomial
of second degree, since xy has degree 2.
Diagonal
A line segment
connecting any two vertices of a polygon that are not lying on the
same side of the polygon.
Diameter
A chord passing
through the center of a circle or sphere.
Digit
Any of the ten
Arabic numerals of the decimal system, e.g., 0, 1, 2, 3,
4, 5, 6, 7, 8, 9
Dimension
The number of
coordinates required to locate a point, usually in a plane or a
space.
Discriminant
The algebraic
expression, , associated
to the general quadratic equation . Solutions of a quadratic equation are distinct
real numbers, equal real numbers or conjugate complex numbers when
Quadratic Equation
Distance
The length of
shortest line segment joining the given points.
Distribute
law
An axiom of
a particular formal system that states for a given pair of operators
that one distributes over the other. In arithmetic (or algebra)
the multiplication is distributive over addition, in symbolically
. This
important and useful law allows to replace an expression with parenthesis
for an equivalent one without it, allowing simplification of expression
in algebra.
Removing Parenthesis.
Division
The inverse
operation of multiplication. For instance, ,
a is the dividend and b is the divisor.
