f(x)= xsquare minus 9?

Question

What is the domain? How did you get it?

Answer 1

domain is all real numbers.

Answer 2

Well if you graph this equation, how far left and how far right the graph goes, is the domain. How far up and how far down it goes is the range. For example the graph of F(x)=x it's a diagonal line that never ends going from top right to bottom left. The range as well as the domain is (-infinity,+infinity). In your question, F(x)=x^2 - 9, the graph makes a U shape going up from the point (0,-9). Why -9? because there's a minus 9 in the problem. Now the domain is (-infinity,+infinity) because as the graph goes higher, the U shape expands. The range in this equation would be (-9, +infinity) because it starts down at -9 and continuously goes up top and never ends.

Answer 3

all real numbers because there are no restrictions here. any number is capable of being squared and having 9 subtracted from it.

if it was something like the square root, then there would be a restriction because only positive numbers and 0 can be square rooted.

Answer 4

Domain = { x : x Ɛ R the set of Real numbers }