what is the domain of f(x)= (x+4)/(x^3-4x)

Question

anonymous · Answer

set the denominator = 0 and solve.  then say all real numbers except those

anonymous · Answer

but it is like a function equation

anonymous · Answer

$$x^3-4x=0$$
[x(x+2)(x-2)=0\]
$$x=-2,0,2$$ so all real numbers except 
$$\{-2,0,2\}$$

anonymous · Answer

you are asked only for the "domain" right? and you are not allowed to divide by 0. in this case that is all you have to check.  you have to make sure you do not put anything in for x that would make the denominator = 0

anonymous · Answer

i'm trying to learn this domain and range thing so if the question asks what is the domain of a square root i just have to make sure it isnt negative, right?

anonymous · Answer

if it is a fraction, the denominator cannot be 0 as well

mimi_x3 · Answer

No, for a sqaure root it can't be all real values of x

anonymous · Answer

what does that mean?

mimi_x3 · Answer

What do you mean ? all real values of x ?

anonymous · Answer

so if the equation is f(x)= square root of (x)/(1-x). what is the domain?

anonymous · Answer

it cannot be 1 right?

mimi_x3 · Answer

um , idk , is that even possible xD

anonymous · Answer

Yes you are right in saying that it cannot be 1.  If you have a rational number (fraction) x=all real numbers except what makes the denominator 0.  For polynomials the domain of x is all real numbers.  I think i covered most of your question.