SOLUTION: Hi, I had a recent math problem on an online math program that I ultimately got correct through brute force guessing, but I'm not entirely sure how it is supposed to work. It's

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Question 1161128: Hi,
I had a recent math problem on an online math program that I ultimately got correct through brute force guessing, but I'm not entirely sure how it is supposed to work. It's difficult to describe in words, so I have included a link to what the problem looks like and my confusion with it. I am asked to describe the intervals that the function is decreasing, increasing, and constant at, but I am not sure how the answers match up with what the graphed function seems to indicate.
Image of graph and more detailed questions: https://i.imgur.com/JI03bW3.png
Thank you very much.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

When the program says "the function is increasing on the interval [2,3]", it means the function is going uphill when 2+%3C=+x+%3C=+3. So if x is between 2 and 3, inclusive of both endpoints, then the function is going uphill. By "uphill", I mean you go upward as you read from left to right.

In contrast, the portion -2+%3C=+x+%3C=+2 is decreasing because the graph is going downill (as we read from left to right) for this interval. That's how they got the answer [-2,2]

The function is completely flat when x is between 3 and 5, so the interval would be 3+%3C=+x+%3C=+5 which is shortened to [3,5]

So in summary, we look at where the graph is going uphill, downhill or is flat. Then we record the x values to set up the proper intervals.