domain math, how to find the domains in math, what is a parent function in math, what is a domain in algebra, domain of a square root function, what is a parent function, math domain function, domain in math, what is a domain in math, how do you find the domain of a function, what is domain in algebra, how to find domains of functions, find math domains, domain of a square root, what is the domain in algebra, how do you find the domain of a square root, what is the domain algebra, math domains and functions, what is domain in math, what is the domain in math, what is a math domain, find the domains of functions, domain of a function, algebra, what is a domain?, how to find domains math, find domains in math, domain function, what is the domain math, how to find the domain of a square root, algebra domains of functions

Testing the Domain of a Function

function, domain, denominator

The domain of a function consists of all the possibly input (normally x) values. There are three possible scenarios that result in values not being in the domain:

1. When the denominator (if there is one) is equal to 0.

2. When taking the square root of a negative number

3. When taking the log of a non-positive (negative or 0) number.

Testing these three cases will normally eliminate all value that aren't in the domain. For example, take the function

log(10堀) / (x+4)

Testing the three cases:

The denominator ((x+4) ) is 0 when x = -4. Therefore, -4 is not in the domain.

There is a square root, and the value inside the square root is negative when x < -4. Therefore, x < -4 is not in the domain.

There is a log, and the value is non-positive when x10. Therefore x10 is not in the domain.

So, looking at these three values means the domain is -4 < x < 10.

A good visual technique while eliminating values for the domain is to use a number line and cross out the values that do not work.

<末末末末末末末末末末末末|末末末末末末末末末末末末末>
                                       0                                                  


< XXXXXXXXXXXXX|末末末末|末末末末末末末|XXXXXXXXX  >
                        -4            0                         10                     

function, domain, denominator

With which subject do you need help?


Math Made Easy will never share or sell your information.
© Copyright MME, Inc. 2010 United States. All Rights Reserved.
About Us | Returns, Exchange and Guarantee | Shipping & Handling | Articles | Tutorials | Privacy Policy
| Students | Parents | Educators
how do you find the domain of a square root, what is the domain algebra, math domains and functions, what is domain in math, what is the domain in math, what is a math domain, find the domains of functions, domain of a function, algebra, what is a domain?, how to find domains math, find domains in math, domain function, what is the domain math, how to find the domain of a square root, algebra domains of functions