Wednesday

April 16, 2014

April 16, 2014

Posted by **Kennedy** on Monday, December 15, 2008 at 3:30pm.

i know that domain is the x value but how can i tell what it is?

y=1/x

y=3/x^2-49

y{x}

y=square root of 3-x

y=[x].

- Math -
**Reiny**, Monday, December 15, 2008 at 4:37pmin plain English, the domain is the value of x that you may use in your given function to return a value

in your first one, remember that we cannot divide by zero, so x=0 is the only value which would not work

so the domain would be the set of real numbers, except x is not equal to zero

for your second, y = 3/(x^2-49)

the trouble arises when x = ± 7

do you think you can state the domain?

another case where difficulty arises is when your function tries to take the square root, (or any even root) of a negative number.

e.g. your third one:

y = √(3-x)

your domain would be all real values of x which would make (3-x) ≥ 0

- Math -
**Kennedy**, Monday, December 15, 2008 at 4:45pmi have a question.... when i get a function, how do i konw if it has an inverser... for example, y=ab.solute value x, then -2. i plugged in x=ab.solute val. of y, then -2. but how do i know if that is an inverse??

**Related Questions**

MAth - how do i find the domain and range of equations? example: f(x)=ab.solute ...

Pre-Calc - Suppose that f has a domain of A and g has a domain of B. (a). What ...

Small Group Communication - Regulating participation, climate making, and ...

pre-cal - for the given functions f & g find the specified value of the ...

Algebra - Could you please help in finding the domain? Thanxs! Find the domain ...

Math - 1) Let f(x)=9x-2;g(x)=under square root 3x+7. Find each of the following...

Algebra - Could you please check my answers and help me with one? Find the ...

math - For the given functions f & g find the following and state the domain of ...

alg 1 - Quadratic graphs and their properties: Identify the domain and range of ...

math - How can I find the restrictions on the domain for this problem: f(x)=1/x...