Two segments are given on the number line:
B = [10; 20] and
C = [12; 30]. Specify
the smallest possible length of such a segment
A for which the logical expression
\((x \notin B) \rightarrow ((x \in C) \rightarrow (x \in B)) \ vee \neg((x \notin A) \wedge (x \in C))\)
true (i.e. takes the value 1) for any value of the variable
x.