How to Learn Domain,Range and Real Number Of Function Mathematics ?

[Apurbow]

How to Learn Domain,Range and Real Number Of Function Mathematics ?
I have some math Questions for Solving?
1.Find the Domain and range of f(x)= (x+2)?

 

[Greg]

1.Find the Domain and range of f(x)= (x+2)?

$f(x)$ is defined for all real $x$, so the domain is $x\in\mathbb{R}$. The range is $(-\infty,\infty)$.

 

[skeeter]

How to Learn Domain,Range and Real Number Of Function Mathematics ?

Sketching the graph of a function helps one visualize the domain & range.