how do i Write the union (−3,7)∪[3,8] as a single interval.

Question

I'm not really sure how to do this yet and it is very confusing to me how to write it in the correct form at the moment

Answer 1

Union means you take everything from both sets, but no duplicates.

 

-3 is not included in either interval.

3 is included in both intervals, as is the 7.

8 is included in the second interval but not the first.

 

The union is (-3,8]

 

Draw a number line.

-3 is labeled with an open circle.

8 is labeled with a shaded circle.

Everything in between is shaded.