The shape of a roller coaster is modeled by a polynomial function, R(x). Describe how to find the x-intercepts of R(x) and how to construct a rough graph of R(x) so that the engineer can predict when there will be no change in the direction of the coaster. You may create a sample polynomial of degree 3 or higher to use in your explanations. Help?

Question

anonymous · Answer

How would I do this problem if I decided to use x^3?

anonymous · Answer

@ranga @tom982

anonymous · Answer

Help me please?

anonymous · Answer

@AlexandervonHumboldt2 @Compassionate

retireed · Answer

Need a polynomial a little more complex to explain this properly.

Say for example:    x^3+x^2-17x+15

anonymous · Answer

Okay

retireed · Answer

Can you explain what the x-intercepts means to you?

anonymous · Answer

they will be the points at which the line crosses the x-axis?

retireed · Answer

Very good!

anonymous · Answer

Thanks. So, how do we get the x intercepts?

retireed · Answer

It also means where Y equals zero, so these are the roots of the function.

retireed · Answer

Do you know how to find the roots of a function?  By saying factoring?

anonymous · Answer

set it to zero

anonymous · Answer

so, 0 = x^3 + x^2 - 17x + 15?

retireed · Answer

That is the second step, first you need to simplify the polynomial.

something like (ax+b) (cx^2+dx+e)

This a difficult polynomial to determine the first root, so it you have a graphing calculator try to plot the equation.

retireed · Answer

It will look something like this.

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