Question

Find the domain of the exponential function f(x) = -2(3)^x

Answer 1

looks for all real x is good

Answer 2

Domain is what are the allowed values of x.
Here we don't see any restrictions placed on x.
So x can be any real number: x: (-infinity, infinity)
or -infinity < x < infinity

But if for example he had a function such as 1/(x-2). Then x =2 is not allowed because you will be dividing by zero. So the domain will exclude x = 2.

Answer 3

soo i can put all reall numbers for awnser

Answer 4

Yes. There are different ways of stating that fact. Which one you use depends on what the instructor expects you to do or what is in the multiple choice answers.

Domain is all real numbers
x: (-infinity, infinity)
-infinity < x < infinity

are three different ways of saying the same thing.