Equation of Tangent and Normal
On this page, we look at how to find the equation of a tangent and the equation of a normal to a curve. A tangent to a curve at a point is the straight line through that point whose gradient is equal to the gradient of the curve at that point. A normal to a curve at a point is the straight line through that point that is perpendicular to the tangent. To find either line, we use the derivative and the coordinates of...