Simple Range

What's the difference between $[0, \infty)$ and $(0,\infty)$ ? I became confused and clicked the wrong option.

haha, thank you for you and Sandeep... see you soon... (wait,haha):)

the domain of a function is the place where a function is defined. In this case, we are treating the exponential function defined in $\mathbb{R}$ and this is the domain of the exponential function and the range is $(0,\infty)$ (set of values got). I'm going to give you some examples, let the function $f: \mathbb{C} \longrightarrow \mathbb{C}, \space / \space f(x) = e^x \space \forall x \in \mathbb{C}$ . In this case, the domain of the exponential function is $\mathbb{C}$ and the codomain(place where arrives the images of the elements) is $\mathbb{C}$ too. In this case,the range of this function(set of values got) is the set $\{z \in \mathbb{C} \space / \space \exists x \in \mathbb{C} \space \text{ and } \space e^x = z\} = \mathbb{C} - \{0\}$ .( It depends on the teachers and schools the next subparagraph . The image set of a function is sometimes the codomain and other times is the range...) Other example, $f: \mathbb{R} \longrightarrow \mathbb{Z}, \text{ such that } f(x) = \lfloor {x} \rfloor \text{ for all } x \in \mathbb{R}$ . Here the domain of the floor function is $\mathbb{R}$ , and the codomain coincides with the range in this case, which is $\mathbb{Z}$ ... If you have more doubts or you want more examples, ask me please...

Note.- I can't believe that you and Anish are able to post incredibles and some very difficult problems, and not to know these simple definitions. Anish had some doubts about intervals...It's unbelievable for me. For this reason I think is essential on Brilliant to talk about Topology, which is other fundamental branch of maths, like algebra, geometry, Calculus and Statics...