Question

how do i find the domain of a function

Answer 1

mainly by exclusion of "inputs" that don't give you a valid "output"

Answer 2

Another way to do it is to find the inverse of the function. The range of the inverse is the domain of the original function.

Answer 3

example: f(x)=1/x
method 1. We cannot divide by zero, but x can be anything else. So, the domain is
(-infinity,0)U(0, infinity)

Answer 4

I would say it shows the limit of the graph for example if you draw a sine graph the Domain (x-axis) would be negative infinite to infinite. Range would be -1 to 1.