# Math Help - Calculus: Differentiation

1. ## Calculus: Differentiation

1. State the definition of the derivative, and give two interpretations of it.
2. Find the values of x at which the curve y= f(x) has a horizontal tangent.
If you can help me, I would gradually appreciate it

2) This question makes no sense. You get a horizontal tangent when $\frac{dy}{dx}=0$. To work it out the function $y=f(x)$ has to be known (I think).