# Math Help - Conditions for cubic equation to have horizontal tangent.

1. ## Conditions for cubic equation to have horizontal tangent.

Can anyone explain how to do these two problems? I don't understand them at all:

Thanks

2. What is the condition to have a horizontal tangent?

3. slope of the function = 0...why?

4. In other words, $f'(x) = 0$. I assume you can find the derivative of $f(x)$. Then, find values of $a$, $b$, $c$ for which the equation $f'(x) = 0$ has exactly two, exactly one, or no solutions.

5. Originally Posted by colerelm1
slope of the function = 0...why?
You are meant to think a little bit harder than this when asked a leading question.