Find the equation of the normal to
y = 2x3 – x2 + 3 at (1, 4).
finding the slope of the tangent by differentiating the curve
m = 4 at (1,4)
normal is perpendicular to tangent so, m1m2 = – 1
equation of normal is given by y – y1 = m(normal)(x – x1)
x + 4y = 17