Question
Union and intersection of intervalsA and B are sets of real numbers defined as follows:A = {y | y > 1}B = {y | y ≤ 6}Write A ∪ B and A ∩ B using interval notation. If a set is empty, write ∅.
Answers
First translate each set:
The union contains values in either set. Values at or below 6 are in , while values above 6 are in , so together the sets cover every real number.
The intersection contains only values in both sets. A number must be greater than 1 and less than or equal to 6, giving . The parenthesis at 1 reflects the strict inequality ; the bracket at 6 reflects .
Evidence boundary
This answer is limited to the exact sets A = {y | y > 1} and B = {y | y ≤ 6}. Endpoint inclusion follows the strict and non-strict inequalities in that version; no endpoints from other ALEKS variants are used.
Sources
These references support the concepts and methods used in the explanation above.