Given a function f(x), and two points on the curve (a, f(a)) and (b, f(b)) the line joining these two points is called a secant line of f. (Not to be confused with the trigonometric secant (sec) ...

As a tangent is a straight line it is described by an equation in ... You are usually given the point - it's where the tangent meets the circle. To find the gradient use the fact that the tangent ...

ie the line cuts the circle at two distinct points, the line is a tangent to the circle or the line misses the circle. To work out which case you have, use algebra to work out how many points of ...