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To find equation of the tangent to the curve at a particular point:

(1) Find the gradient of the curve (i.e. differentiate y with respect to x).
(2) If the gradient is in terms of x, sub the x coordinate of the point to get the value of the gradient.
(3) Use the equation y = mx + c or y - y1 = m(x - x1) to find the equation of the tangent.

To find equation of the normal to the curve at a particular point:

(1) First, find the gradient of the tangent
(2) Gradient of Normal, m2 = -1/m1
(3) Use the equation y = mx + c or y - y1 = m(x - x1) to find the equation of the normal.