Summary: An introductory explanation on how to use interval notation (versus set notation)
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Interval notation is another method for writing domain and range.
In set builder notation braces (curly parentheses {} ) and variables are used to express the domain and range. Interval notation is often considered more efficient.
In interval notation, there are only 5 symbols to know:
To use interval notation:
Use the open parentheses ( ) if the value is not included in the graph. (i.e. the graph is undefined at that point... there's a hole or asymptote, or a jump)
If the graph goes on forever to the left, the domain will start with (
Use the brackets [ ] if the value is part of the graph.
Whenever there is a break in the graph, write the interval up to the point. Then write another interval for the section of the graph after that part. Put a union sign between each interval to "join" them together.
Now for some practice so you can see if any of this makes sense.
Write the following using interval notation:
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Write the domain and range of the following in interval notation:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range:
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Domain:
Range: