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# Cubic Graphs have i done them correctly watch

1. (Original post by junayd1998)
Yes that's correct
2. (Original post by Trapz99)
Yes that's correct
Woo! Thanks
3. (Original post by junayd1998)
...
Close.

In your second graph, it is important the the curve goes through the roots, yours goes underneath them.

And when they go off to infinity, the curve just gets steeper, it does not start to become shallower as you have for x from 2 to 5 in the first graph, and from x=4 in the second.

Here's the actual first graph:

4. I believe the second one is ever so slightly wrong. In between x = 0 and x = -1 you aren't crossing the x axis which also means your line isn't touching the X axis at 0 or -1. If x = -0.5 you get a value just over 1 for y.

Similar issue on the top graph as well actually. x = -1 gives y = 3.

Basically your curves need to be more pronounced.
5. (Original post by junayd1998)
Woo! Thanks
Actually no, in your second graph the curve needs to go through (-1,0), (0,0) and (4,0). Between (-1,0) and (0,0) the value of y should be positive . So it goes up and then down.
6. (Original post by ghostwalker)
Close.

In your second graph, it is important the the curve goes through the roots, yours goes underneath them.

And when they go off to infinity, the curve just gets steeper, it does not start to become shallower as you have for x from 2 to 5 in the first graph, and from x=4 in the second.

Here's the actual first graph:

Oh so the second one has to go slightly above the x axis?

7. (Original post by Trapz99)
Actually no, in your second graph the curve needs to go through (-1,0), (0,0) and (4,0). Between (-1,0) and (0,0) the value of y should be positive . So it goes up and then down.
Like this ??

8. (Original post by junayd1998)
Oh so the second one has to go slightly above the x axis?

Yes.

But you also want to take care of the curvature at the ends.
9. (Original post by ghostwalker)
Yes.

But you also want to take care of the curvature at the ends.
Oh, yes it needs to be more of a curve.
10. Here's the actual second graph:

Notice how the ends just get steeper.

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