Reconstruct f from its First Derivative

Reconstruct `f` from its First Derivative

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Until now, we have addressed the question, "Given `f(x)`, what can we know about `f'(x)`?" But now we will reverse it.

Given the graph of `f'(x)` can we deduce what `f(x)` looks like?

You are given the graph of `f'(x)`, and your task is to reconstruct the graph of `f(x)`.
Once you can do this well, you are ready for the first derivative test.

Explore

The graph of `f'(x)` is shown in red. Drag the blue points up and down so that together they follow the shape of the graph of `f(x)`. As a help, the three large green points are points on the graph of `f(x)`.
Are the three green points necessary? Theoretically, could you reconstruct `f(x)` from only one green point? from no green points?
How can you tell where the `f`-graph is increasing? decreasing?
How can you tell where the `f`-graph has a max? a min?
What information in the `f'`-graph would tell you the point where `f` increases the fastest?
Keep practicing until you can get your accuracy consistently in the 90's!