# Definition of the Derivative

- Author:
- Andy Wain, Jeff Willets

Questions to think about and discuss with your neighbor:
1) What is the horizontal distance between P and A? (not a number, an expression)
2) What is the vertical distance between P and A? (If you need a hint, click the check box)
3) What is the equation for the slope of the red (secant) line? Does this seem like anything we've heard of?
4) What happens as we let h get larger or smaller? (Use the slider at the top)
5) Click on the Tangent Line checkbox. What would be an expression for the slope of the Tangent Line?
6) So what's the whole point here?