Finding the domain (VERY EASY I'M SURE!)

[jennyskywalker]

If someone could just walk me through step by step how to do this I'm sure I would understand so much better:
Find the domain of f(x) = √x³+3x and compute f(-1), f(2).

 

[Deleted member 4993]

If someone could just walk me through step by step how to do this I'm sure I would understand so much better:
Find the domain of f(x) = √x³+3x and compute f(-1), f(2).

For a quick review go to:

http://www.purplemath.com/modules/fcns2.htm

also look at:

http://www.purplemath.com/modules/rtnldefs.htm

Realize that √[f(x)] is "complex" (not real) when f(x)<0, you should be able to calculate the domain of the given function.