let f: R→R; f(x)=x².
Evaluate the two sets f((-1, 1)) and f⁻¹((0, 1)).
The definitions of interval notation.
[a, b] = {x ∈ R | a ≤ x ≤ b}
(a, b] = {x ∈ R | a < x ≤ b}
[a, b) = {x ∈ R | a ≤ x < b}
(a, b) = {x ∈ R | a < x < b}
Where R denotes the set of real numbers.