Definition Of Domain In Math

Online Tutoring Is The Easiest, Most Cost-Effective Way For Students To Get The Help They Need Whenever They Need It.

SIGN UP FOR A FREE TRIAL




Domain is set of values of independent variable for which a function is defined. In simple words, Domain is the set of input values given to a function.  The domain of a function is the set of input values which allows the function to work. Mostly domain is the set of all real numbers.  In a relation, domain is a set of x coordinate of the ordered pair of that relation. For example, in a relation (3, 4), (9, 7), (12, 15) the domain of the relation is 3, 9 and 12.
 
Example 1: (-4, 2) (2,-8) (5,-7) (8,-10). What is the domain of the set of ordered pairs given?

Solution: The domain of a set of ordered pairs is the set of x-coordinates.
 In this set of ordered pairs, the x-coordinates are -4, 2, 5, and 8.
 Therefore the domain is {-4, 2, 5, 8}


Example 2: Given the range {-1, -2, 2}, what is the domain for the relation y = x - 3?

Solution: First, rewrite the equation in terms of x.
 y = x – 3
 y + 3 = x -3 + 3
 x = y + 3
 Next, substitute range values in for y in the equation x = y + 3.
 When y = -1 then x = -1 + 3 = 2
 Similarly when y = -2 then x = 1
 When y = 2 then x = 5
 Therefore, the domain is {2, 1, 5}.



HAVE A QUESTION? Chat With Our Tutoring Experts Now