If R is the set of real numbers and Q is the set of rational numbers, then what is `R Q`?

Explanation

R = set of real numbers
`= {x :x in R}`
= {x : x is rational or x is irrational}
while Q = {x : x `in` rational number}
Now, R - Q = a set whose elements are real numbers but not rational numbers
= {x : x is an irrational number}
Therefore, `R - Q=` set of irrational numbers.