What is the increasing and decreasing intervals of this graph?

Answer:
A function is increasing on an interval if its slope is positive on that interval. That is, if you follow it to the right, it'll go up.
The graph increases at 3 and decreases at 1
A function is decreasing on an interval if its slope is negative on that interval. That is, if you follow it to the right, it'll go down.
Step-by-step explanation:
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