Question

How do you express intervals as inequalities such as (-4,-2)?

Answer 1

`-4< x< -2` `:x in RR`

Explanation:

Let's assume we are dealing with the interval between `-4` and `-2` on the real line, exclusive of the upper and lower end points.

This means we are considering all points `x` on the real line between -4 and -2 exclusive. That is all points `x in R` where `-4< x<-2`

NB: If we were considering the interval including the upper and lower end points, this could be written: `-4 <= x <= -2` `:x in RR`