The domain of a relation or function are all the values of x (elements of reals numbers). Each x-value has a corresponding y value.
Example:
f (x) = 2x + 3 Note: f(x) is y-value for the given x.
f (4) = 2 (4) + 3
f (4) = 8 + 3
f (4) = 11
This means that if x = 4, then y = 11
The corresponding y-values is the range (elements of real numbers)
If all domain and range are elements of real numbers, then:
Domain = {x/x is an ∈ of Real Numbers}
Domain = (-∞ , +∞)
Range = {y/y is an ∈ or Real Numbers}
Range = (-∞ , +∞)
