Practice Union in Math
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
The union of sets A and B is the set of all elements that belong to A, to B, or to both, written A \cup B.
Pour both sets into one container and remove duplicates. Everything from either pile ends up in the union — this is the OR operation for sets.
Example 1
easyLet A = \{1, 3, 5\} and B = \{2, 3, 4\}. Find A \cup B.
Example 2
mediumLet A = \{x \in \mathbb{R} : x > 2\} and B = \{x \in \mathbb{R} : x < 5\}. Express A \cup B in interval notation.
Example 3
easyLet P = \{a, b, c\} and Q = \{c, d, e\}. Find P \cup Q.
Example 4
easyFind A \cup B if A = \{a, b, d\} and B = \{b, c, d, e\}.