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 $\displaystyle \frac{dy}{dx}=0$. To work it out the function $\displaystyle y=f(x)$ has to be known (I think).