1. How do you find the gradient of a curved graph?
Find the gradient of the tangent (a line that just touches the curve).
2. What is a normal?
A normal to a curve at a particular point is a line a right angles (perpendicular) to the tangent at that point.
3. What is the equation of the tangent to a parabola at its base point?
The equation of the tangent to the turning point of a parabola will be of the form y = c (i.e. a horizontal line)