The set {x ∈ R : 1 ≤ x < 2} can be written as ______________
Given set:
\[ \{x \in \mathbb{R} : 1 \le x < 2\} \]
This means:
- 1 is included in the set
- 2 is not included in the set
Hence, in interval notation, the set is written as:
\[ [1,2) \]
Answer
\[ \boxed{[1,2)} \]