Mathematics
OpenStudy (anonymous):

How can you tell what a real number is?

OpenStudy (anonymous):

it is basically any number

OpenStudy (anonymous):

decimals while numbers anything or all

OpenStudy (anonymous):

So how would you be able to estimate a domain and range if it's possible to have all real numbers?

OpenStudy (anonymous):

well u just say the set of real numbers$\in R$

OpenStudy (anonymous):

Ohhh!!! drr... Thank you!

OpenStudy (dumbcow):

or you can use $(-\infty,\infty)$

OpenStudy (anonymous):

To answer that question, it is better to know what are considered NON-REAL. Complex numbers(square root of a negative number), numbers resulting from division by zero are examples of NON-REAL numbers. Anything else that is well defined in Mathematics (irrational,pi, e, fractions, integers) are considered REAL.