determine the intervals on which the function is increasing, decreasing and constant

Answer:
Step-by-step explanation:
The function goes up to the right until it gets to the vertex at x=0. Then it goes down to the right. That is, it is ...
increasing from -∞ to 0 (not including 0)
decreasing from 0 to +∞ (not including 0)
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At x=0, the function is neither increasing nor decreasing, so x=0 is not part of either interval.